Question
Read the following passage and answer the questions given below: elation between the height of the plant $\left(y^{\prime}\right.$ in cm $)$ with respect to its exposure to is governed by the following equation  $y=4 x-\frac{1}{2} x^2$, where ' $x$ ' is the number of days exposed to the sunlight, for $x \leq 3$

Image

(i) Find  the rate of growth of the plant with respect to the number of days exposed to the sunlight.

(ii) Does the rate of  growth of the plant increase or decrease in the first three days? 
What will be the height of the plant after 2 days?

Answer

$y=4 x-\frac{1}{2} x^2$ 

(i) The rate of growth of the plant with respect to the number of days exposed to sunlight is given by $\frac{d y}{d x}=4-x$

(ii) Let rate of growth be represented by the function $g(x)=\frac{d y}{d x}$

Now, $g^{\prime}(x)=\frac{d}{d x}\left(\frac{d y}{d x}\right)=-1<0$

$\Rightarrow g(x)$ decreases.

So the rate of growth of the plant decreases for the first three days.

Height of the plant after 2 days is $y=4 \times 2-\frac{1}{2}(2)^2=6 \mathrm{~cm}$.

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Using the concept of matrices and determinants, answer the following questions.
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  1. ₹ 350
  2. ₹ 300
  3. ₹ 500
  4. ₹ 400
  1. What is the award money for Punctuality?
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  2. ₹ 280
  3. ₹ 450
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  2. ₹ 400
  3. ₹ 300
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  1. If a matrix P is both symmetric and skew-symmetric, then |P| is equal to:
  1. 1
  2. -1
  3. 0
  4. None of these.
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A trust fund has $₹ 35000$ that must be invested in two different types of bonds, say $\mathrm{X}$ and $\mathrm{Y}$. The first bond pays $10 \%$ interest p.a. which will be given to an old age home and second one pays $8 \%$ interest p.a. which will be given to WWA (Women Welfare Association). Let A be a $1 \times 2$ matrix and B be a $2 \times 1$ matrix, representing the investment and interest rate on each bond respectively.

Image

(i) Represent the given information in matrix algebra.

(ii) If ₹ 15000 is invested in bond $\mathrm{X}$, then find total amount of interest received on both bonds?

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OR

If the amount of interest given to old age home is ₹500, then find the amount of investment in bond Y.

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Using the above information and concept of determinants, answer the following questions.
  1. If the vertices ofoneof the smaller equilateral triangle are (0, 0), $(3,\sqrt{3})$ and $(3,-\sqrt{3}),$ then the area of such triangle is:
  1. $\sqrt{3}\text{ sq}.\text{units}$
  2. $2\sqrt{3}\text{ sq}.\text{units}$
  3. $3\sqrt{3}\text{ sq}.\text{units}$
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  2. $50\sqrt{3}\text{ sq}.\text{units}$
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  2. $\text{x}=1+\sqrt3$
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  1. Let A(a, 0), B(0, b) and C(1, 1) be three points. If $\frac{1}{\text{a}}+\frac{1}{\text{b}}=1,$ then the three points are:
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The relation between the height of the plant ( $\mathrm{y}$ in $\mathrm{cm}$ ) with respect to exposure to sunlight is governed by the following equation $\mathrm{y}=4 \mathrm{x}-\frac{1}{2} \mathrm{x}^2$ where $\mathrm{x}$ is the number of days exposed to sunlight.

Image

(i) Find the rate of growth of the plant with respect to sunlight.

(ii) What is the number of days it will take for the plant to grow to the maximum height?

(iii) Verify that height of the plant is maximum after four days by second derivative test and find the maximum height of plant.

OR

What will be the height of the plant after 2 days?

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  1. $\text{x}+\text{y}+\frac{\pi}{2}=10$
  2. $\text{x}+\text{2y}+\frac{\pi\text{x}}{2}=10$
  3. $\text{2x}+\text{2y}=10$
  4. $\text{x}+\text{2y}+\frac{\pi}{2}=10$
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  1. $\text{A}=\text{x}-\frac{\text{x}^3}{8}-\frac{\text{x}^2}{2}$
  2. $\text{A}=\text{5x}-\frac{\text{x}^2}{8}-\frac{\pi\text{x}^2}{8}$
  3. $\text{A}=\text{x}+\frac{\pi\text{x}^3}{8}-\frac{\text{3x}^2}{8}$
  4. $\text{A}=\text{5x}+\frac{\text{x}^3}{2}+\frac{\pi\text{x}^2}{8}$
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  2. $\frac{20}{4-\pi}$
  3. $\frac{20}{4+\pi}$
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  1. $\frac{30}{4+\pi}$
  2. $\frac{30}{4-\pi}$
  3. $\frac{50}{4-\pi}$
  4. $\frac{50}{4+\pi}$
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  1. $\frac{10}{4+\pi}$
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  3. $\frac{20}{4+\pi}$
  4. $\frac{20}{4-\pi}$
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Based on the above information, answer the following questions.
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  3. $\begin{bmatrix}3\\-3\end{bmatrix}$
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  1. 2
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  3. 3
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  1. 3
  2. -3
  3. -5
  4. 5
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  1. 1
  2. 2
  3. -2
  4. -1
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  1. 1
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  1. $\frac{4\text{x}^3}{3}+\frac{2}{2}\pi\text{r}^2$
  2. $\frac{2\text{x}^2}{3}+\frac{4}{3}\pi\text{r}^2$
  3. $\frac{2\text{x}^3}{3}+\frac{4}{3}\pi\text{r}^3$
  4. $\frac{2}{3}\text{x}+\frac{4}{3}\pi\text{r}$
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  3. $\sqrt{\frac{\text{k}^2-4\pi}{6}}$
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  2. $\sqrt{\frac{\text{k}^2}{54+4}}$
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Let X and Y denote the total points scored by team A and B respectively, after two games.

Based on the above information, answer the following questions.

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  2. $\frac{1}{6}$

  3. $\frac{1}{3}$

  4. None of these
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  2. $\frac{1}{3}$

  3. $\frac{1}{6}$

  4. $\frac{3}{10}$

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  1. $\frac{1}{4}$

  2. $\frac{5}{12}$

  3. $\frac{1}{20}$

  4. $\frac{11}{20}$

  1. P(X = Y) is equal to:
  1. $\frac{11}{100}$

  2. $\frac{1}{3}$

  3. $\frac{29}{100}$

  4. $\frac{1}{2}$

  1. P(X + Y = 8) is equal to:
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  2. $\frac{5}{12}$

  3. $\frac{13}{36}$

  4. $\frac{7}{12}$

A differential equation is said to be in the variable separable form if it is expressible in the form f(x) dx = g(y) dy.
The solution of this equation is given by
$\int\text{f(x)dx}=\int\text{g(y)dy}+\text{c},$ where c is the constant of integration.
Based on the above information, answer the following questions.
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  1. 2
  2. -2
  3. 3
  4. -4
  1. The differential equation $\frac{\text{dy}}{\text{dx}}=\frac{\sqrt{1-\text{y}^2}}{\text{y}}$ determines a family of circle with.
  1. Variable radii and fixed centre (0, 1)
  2. Variable radii and fixed centre (0, -1)
  3. Fixed radius 1 and variable centre on x-axis
  4. Fixed radius 1 and variable centre on y-axis
  1. If = y'+ 1, y(0) = 1, then y (In 2) =
  1. 1
  2. 2
  3. 3
  4. 4
  1. The solution of the differential equation $\frac{\text{dy}}{\text{dx}}=\text{e}^\text{x-y}+\text{x}^2\text{e}^\text{-y}$ is:
  1. $\text{e}^\text{x}=\frac{\text{y}^3}{3}+\text{e}^\text{y}+\text{c}$
  2. $\text{e}^\text{y}=\frac{\text{x}^2}{3}+\text{e}^\text{x}+\text{c}$
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  1. If $\frac{\text{dy}}{\text{dx}}=\text{y}\sin2\text{x},\ \text{y}(0)=1,$ then its solution is:
  1. $\text{y}=\text{e}^{\sin^2}\text{x}$
  2. $\text{y}={\sin^2}\text{x}$
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Three schools A, B and C organized a mela for collecting funds for helping the rehabilitation of flood victims. They sold handmade fans, mats, and plates from recycled material at a cost of ₹ 25 , ₹ 100 and ₹ 50 each. The number of articles sold by school A, B, C are given below.

Image

(i) Represent the sale of handmade fans, mats and plates by three schools A, B and C and the sale prices (in ₹) of given products per unit, in matrix form.

(ii) Find the funds collected by school A, B and C by selling the given articles.

(iii) If they increase the cost price of each unit by $20 \%$, then write the matrix representing new price.

OR

Find the total funds collected for the required purpose after $20 \%$ hike in price.