Question
A function f(x) is said to be continuous in an open interval (a, b), if it is continuous at every point in this interval.
A function f(x) is said to be continuous in the closed interval [a, b), if f(x) is continuous in (a, b) and $\lim\limits_{\text{x}\rightarrow0}\text{f}(\text{a}+\text{h})=\text{f}(\text{a})$ and $\lim\limits_{\text{x}\rightarrow0}\text{f}(\text{b}-\text{h})=\text{f}(\text{b})$
If function $\text{f}(\text{x})=\begin{cases}\frac{\sin(\text{a}+1)\text{x}+\sin\text{x}}{\text{x}}&,\text{x}<0\\\text{c}&,\text{x}=0\\\frac{\sqrt{\text{x}+\text{bx}^2}-\sqrt{\text{x}}}{\text{bx}^{\frac{3}{2}}}&,\text{x}>0\end{cases}$ is continuous at x = 0, then answer the following questions.
  1. The value of a is:
  1. $-\frac{3}{2}$
  2. $0$
  3. $\frac{1}{2}$
  4. $-\frac{1}{2}$
  1. The value of b is:
  1. 1
  2. -1
  3. 0
  4. Any real number.
  1. The value of c is:
  1. $1$
  2. $\frac{1}{2}$
  3. $-1$
  4. $-\frac{1}{2}$
  1. The value of a + c is:
  1. 1
  2. 0
  3. -1
  4. -2
  1. The value of c - a is:
  1. 1
  2. 0
  3. -1
  4. 2

Answer

$\text{L.H.L.}(\text{at x})=\lim\limits_{\text{x}\rightarrow0}\frac{\sin(\text{a}+1)\text{x}+\sin\text{x}}{\text{x}}\Big(\frac{0}{0}\text{ form}\Big)$ Using L' Hospital rule, we get $\text{L.H.L.} (\text{at x} = 0)$ $=\lim\limits_{\text{x}\rightarrow0}(\text{a}+1)\cos(\text{a}+1)\text{x}+\cos\text{x}=\text{a}+2$ $\text{R.H.L.} (\text{at x} = 0)=\lim\limits_{\text{x}\rightarrow0}\frac{\sqrt{\text{x}+\text{bx}^2}-\sqrt{\text{x}}}{\text{bx}^\frac{3}{2}}=\lim\limits_{\text{x}\rightarrow0}\frac{\sqrt{1+\text{bx}}-1}{\text{bx}}$ $=\lim\limits_{\text{x}\rightarrow0}\frac{1}{\sqrt{1+\text{bx}}+1}=\frac{1}{2}$ Since,f(x) is continuous at x = 0. $\therefore$ From (i) and (ii), we get $\text{a}+2=\text{c}=\frac{1}{2}\Rightarrow\text{a}=-\frac{3}{2},\text{c}=\frac{1}{2}$ Also, value of b does not affect the continuity of f(x), so b can be any real number.
  1. (a) $-\frac{3}{2}$
  1. (d) Any real number.
  1. (b) $\frac{1}{2}$
  1. (c) -1
Solution:
$\text{a}+\text{c}=-\frac{3}{2}+\frac{1}{2}=-1$
  1. (d) 2
Solution:
$\text{c}-\text{a}=\frac{1}{2}+\frac{3}{2}=2$

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Image

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(ii) Find the probability that mother is at right end, given that son and daughter are together.

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 Based on the above information, answer the following questions.
  1. If $l_{1} ,m_1, n_{1},$ and $l_2, m_2, n_2$ are the direction cosines of $L_1$ and $L_2$ respectively, then $L_1$ will be perpendicular to $L_2,$ iff:
  1. $l_1l_2 + m_1m_2 + n_1n_2 = 0$
  2. $l_1m_2 + m_1l_2 + n_1n_2 = 0$
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  4. None of these
  1. If $l_1, m_1, n_1$ and $l_2, m_2, n_2$ are direction cosines of $L_1$ and $L_2$ respectively, then $L_1$ will be parallel to $L_2,$ iff:
  1. $l_1l_2 + m_1m_2 + n_1n_2 = 0$
  2. $l_1m_2 + m_1l_2 + n_1n_2 = 0$
  3. $\frac{\text{l}_1}{\text{l}_2}=\frac{\text{m}_1}{\text{m}_2}=\frac{\text{n}_1}{\text{n}_2}$
  4. $m_1n_2 + m_2n_2 + l_1l_2 = 0$
  1. The coordinates of the foot of the perpendicular drawn from the point $A(1, 2, 1)$ to the line joining $B(1, 4, 6)$ and $C(5, 4, 4),$ are:
  1. $(1, 2, 1)$
  2. $(2, 4, 5)$
  3. $(3, 4, 5)$
  4. $(3, 4, 5)$
  1. The direction ratios of the line which is perpendicular to the lines with direction ratios proportional to $(1, -2, -2)$ and $(0, 2, 1)$ are:
  1. $ < 1, 2, 1 > $
  2. $ < 2,-1, 2 > $
  3. $ < -1,2, 2 > $
  4. None of these
  1. The lines $\frac{\text{x}-2}{3}=\frac{\text{y}+1}{-2}=\frac{\text{z}-2}{0}$ and $\frac{\text{x}-1}{1}=\frac{\frac{\text{y}+3}{2}}{\frac{3}{2}}=\frac{\text{z}+5}{2}$ are:
  1. Parallel.
  2. Perpendicular.
  3. Skew lines.
  4. Non-intersecting.
Let $\text{A}=\begin{bmatrix}1&0\\2&1\end{bmatrix},$ and $U_1, U_2$ are e first and second columns respectively of a $2 \times 2$ matrix $U.$ Also, let the column matrices $U_1$ and $U_2$ satisfying $\text{AU}_1=\begin{bmatrix}1\\0\end{bmatrix}$ and $\text{AU}_2=\begin{bmatrix}2\\3\end{bmatrix}.$ Based on the above information, answer the following questions.
  1. The matrix $U_1 + U_2$​​​​​​​ is equal to:
  1. $\begin{bmatrix}1\\-1\end{bmatrix}$
  2. $\begin{bmatrix}2\\-2\end{bmatrix}$
  3. $\begin{bmatrix}3\\-3\end{bmatrix}$
  4. $\begin{bmatrix}4\\-4\end{bmatrix}$
  1. The value of $|U|$ is:
  1. $2$
  2. $-2$
  3. $3$
  4. $-3$
  1. If $\text{X}=\begin{bmatrix}3&2\end{bmatrix}\text{U}\begin{bmatrix}3\\2\end{bmatrix},$ then the value of $|X| =$
  1. $3$
  2. $-3$
  3. $-5$
  4. $5$
  1. The minor of element at the position $a_{22}$ in $U$ is:
  1. $1$
  2. $2$
  3. $-2$
  4. $-1$
  1. If $\text{U}=[\text{a}_\text{ij}]_{2\times2},$ then the value of $a_{11}A_{11 }+ a_{12}A_{12},$ where $A_{ij}$ denotes the cofactor of $a_{ij},$ is:
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  2. $2$
  3. $-3$
  4. $3$
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  2. 2x + y + z = 8
  3. x + y + 2z = 5
  4. x + y + z = 5
  1. The magnitude of the normal to the plane on which students of school Bare seated, is:
  1. $\sqrt{5}$
  2. $\sqrt{6}$
  3. $\sqrt{3}$
  4. $\sqrt{2}$
  1. The intercept form of the equation of the plane on which students of school Bare seated is:
  1. $\frac{\text{x}}{6}+\frac{\text{y}}{6}+\frac{\text{z}}{6}=1$
  2. $\frac{\text{x}}{3}+\frac{\text{y}}{(-6)}+\frac{\text{z}}{6}=1$
  3. $\frac{\text{x}}{3}+\frac{\text{y}}{6}+\frac{\text{z}}{6}=1$
  4. $\frac{\text{x}}{3}+\frac{\text{y}}{6}+\frac{\text{z}}{3}=1$
  1. Which of the following is a student of school B?
  1. Mohit sitting at (1, 2, 1)
  2. Ravi sitting at (0, 1, 2)
  3. Khushi sitting at (3, 1, 1)
  4. Shewta sitting at (2, -1, 2)
  1. The distance of the plane, on which students of school Bare seated, from the origin is:
  1. 6 units
  2. $\frac{1}{\sqrt{6}}\text{ units}$
  3. $\frac{5}{\sqrt{6}}\text{ units}$
  4. $\sqrt{6}\text{ units}$
Ramesh, the owner of a sweet selling shop, purchased some rectangular card board sheets of dimension 25 cm by 40 cm to make container packets without top. Let x cm be the length of the side of the square to be cut out from each corner to give that sheet the shape of the container by folding up the flaps.
Based on the above information answer the following questions.
(i) Express the volume (V) of each container as function of x only.
(ii) Find $\frac{d V}{d x}$
(iii) (a) for what value of x, the volume of each container is maximum ?
OR
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Ishaan left from his village on weekend. First, he travelled up to temple. After this, he left for the zoo. After this, he left for shopping in a mall. The positions of Jshaan at different places is given in the following graph.

Based on the above information, answer the following questions.
  1. Position vector of B is:
  1. $3\hat{\text{i}}+5\hat{\text{j}}$
  2. $5\hat{\text{i}}+3\hat{\text{j}}$
  3. $-5\hat{\text{i}}-3\hat{\text{j}}$
  4. $-5\hat{\text{i}}+3\hat{\text{j}}$
  1. Position vector of D is:
  1. $5\hat{\text{i}}+3\hat{\text{j}}$
  2. $3\hat{\text{i}}+5\hat{\text{j}}$
  3. $8\hat{\text{i}}+9\hat{\text{j}}$
  4. $9\hat{\text{i}}+8\hat{\text{j}}$
  1. Find the vector $\overline{\text{BC}}$ in terms of $\hat{\text{i}},\hat{\text{j}}.$
  1. $\hat{\text{i}}-2\hat{\text{j}}$
  2. $\hat{\text{i}}+2\hat{\text{j}}$
  3. $2\hat{\text{i}}+\hat{\text{j}}$
  4. $2\hat{\text{i}}-\hat{\text{j}}$
  1. Length of vector $\overline{\text{AB}}$ is:
  1. $\sqrt{67}\text{ units}$
  2. $\sqrt{85}\text{ units}$
  3. 90 units
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  1. If $\vec{\text{M}}=4\hat{\text{j}}+3\hat{\text{k}},$ then its unit vector is:
  1. $\frac{4}{5}\hat{\text{j}}+\frac{3}{5}\hat{\text{k}}$
  2. $\frac{4}{5}\hat{\text{j}}-\frac{3}{5}\hat{\text{k}}$
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Based on the above information, answer the following questions.
  1. The probability that X = 2 equals.
  1. $\frac{1}{6}$
  2. $\frac{5}{6^2}$
  3. $\frac{5}{3^6}$
  4. $\frac{1}{6^3}$
  1. The probability that X = 4 equals.
  1. $\frac{1}{6^4}$
  2. $\frac{1}{6^6}$
  3. $\frac{5^3}{6^4}$
  4. $\frac{5}{6^4}$
  1. The probability that $\text{X}\geq2$ equals.
  1. $\frac{25}{216}$
  2. $\frac{1}{36}$
  3. $\frac{5}{6}$
  4. $\frac{25}{36}$
  1. The value of $\text{P}(\text{X}\geq6)$ is:
  1. $\frac{5^5}{6^5}$
  2. $1-\frac{5^3}{6^5}$
  3. $\frac{5^3\times61}{6^5}$
  4. $\frac{5^3}{6^4}$
  1. The probability that X > 3 equals.
  1. $\frac{36}{25}$
  2. $\frac{5^2}{6^2}$
  3. $\frac{5}{6}$
  4. $\frac{5^3}{6^3}$
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  1. What is the path of the rocket?
  1. Straight line.
  2. Circle.
  3. Parabola.
  4. None of these.
  1. Which of the following points lie on the path of the rocket?
  1. (0, 1, 2)
  2. (1, -2, 2)
  3. (2, -2, 2)
  4. None of these
  1. At what distance will the rocket be from the starting point (0, 0, 0) in 10 seconds?
  1. 40km
  2. 60km
  3. 30km
  4. 80km
  1. If the position of rocket at certain instant of time is (3, -6, 6), then what will be the height of the rocket from the ground, which is along the xy-plane?
  1. 3km
  2. 2km
  3. 4km
  4. 6km
  1. At certain instant of time, if the rocket is above sea level, where equation of surface of sea is given by 3x - y + 4z = 2 and position of rocket at that instant of time is (1, -2, 2), then the image of position of rocket in the sea is:
  1. $\Big(\frac{20}{13},\frac{15}{13},\frac{18}{13}\Big)$
  2. $\Big(\frac{-20}{13},\frac{-15}{13},\frac{-18}{13}\Big)$
  3. $\Big(\frac{20}{13},\frac{-15}{13},\frac{18}{13}\Big)$
  4. None of these
In a play zone, Aastha is playing crane game. It has 12 blue balls, 8 red balls, 10 yellow balls and 5 green balls. If Aastha draws two balls one after the other without replacement, then answer the following questions.
  1. What is the probability that the first ball is blue and the second ball is green?
  1. $\frac{5}{119}$
  2. $\frac{12}{119}$
  3. $\frac{6}{119}$
  4. $\frac{15}{119}$
  1. What is the probability that the first ball is yellow and the second ball is red?
  1. $\frac{16}{119}$
  2. $\frac{8}{119}$
  3. $\frac{24}{119}$
  4. None of these.
  1. What is the probability that both the balls are red?
  1. $\frac{4}{85}$
  2. $\frac{24}{595}$
  3. $\frac{12}{119}$
  4. $\frac{64}{119}$
  1. What is the probability that the first ball is green and the second ball is not yellow?
  1. $\frac{10}{119}$
  2. $\frac{6}{85}$
  3. $\frac{12}{119}$
  4. None of these.
  1. What is the probability that both the balls are not blue?
  1. $\frac{6}{595}$
  2. $\frac{12}{85}$
  3. $\frac{15}{17}$
  4. $\frac{253}{595}$
Two motorcycles A and Bare running at the speed more than allowed speed on the road along the lines $\vec{\text{r}}=\lambda(\hat{\text{i}}+2\hat{\text{j}}-\hat{\text{k}})$ and $\vec{\text{r}}=3\hat{\text{i}}+3\hat{\text{j}}+\mu(2\hat{\text{i}+\hat{\text{j}}+\hat{\text{k}}}),$ respectively. Based on the above information, answer the following questions.
  1. The cartesian equation of the line along which motorcycle A is running is:
  1. $\frac{\text{x}+1}{1}=\frac{\text{y}+1}{2}=\frac{\text{z}-1}{-1}$
  2. $\frac{\text{x}}{1}=\frac{\text{y}}{2}=\frac{\text{z}}{-1}$
  3. $\frac{\text{x}}{1}=\frac{\text{y}}{2}=\frac{\text{z}}{1}$
  4. None of these
  1. The direction cosines of line along which motorcycle A is running, are:
  1. < 1, -2, 1 >
  2. < I, 2, -1 >
  3. $<\frac{1}{\sqrt{6}},\frac{-2}{\sqrt{6}},\frac{1}{\sqrt{6}}>$
  4. $<\frac{1}{\sqrt{6}},\frac{2}{\sqrt{6}},\frac{-1}{\sqrt{6}}>$
  1. The direction ratios of line along which motorcycle Bis running, are:
  1. < 1, 0, 2 >
  2. < 2, 1, 0 >
  3. < 1, 1, 2 >
  4. < 2, 1, 1 >
  1. The shortest distance between the gives lines is:
  1. 4 units
  2. $2\sqrt{3}\text{ units}$
  3. $3\sqrt{2}\text{ units}$
  4. 0 units
  1. The motorcycles will meet with an accident at the point:
  1. (-1, 1, 2)
  2. (2, 1, -1)
  3. (1, 2, -1)
  4. Does not exist