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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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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Now, suppose the given equation is $(1+\sin\text{x})\frac{\text{dy}}{\text{dx}}+\text{y}\cos\text{x}+\text{x}=0.$
Based on the above information, answer the following questions.
  1. The value of P and Q respectively are:
  1. $\frac{\sin\text{x}}{1+\cos\text{x}},\ \frac{\text{x}}{1+\sin\text{x}}$
  2. $\frac{\cos\text{x}}{1+\sin\text{x}},\ \frac{\text{-x}}{1+\sin\text{x}}$
  3. $\frac{-\cos\text{x}}{1+\sin\text{x}},\ \frac{\text{x}}{1+\sin\text{x}}$
  4. $\frac{\cos\text{x}}{1+\sin\text{x}},\ \frac{\text{x}}{1+\sin\text{x}}$
  1. The value of I.F is:
  1. $1-\sin\text{x}$
  2. $\cos\text{x}$
  3. $1+\sin\text{x}$
  4. $1-\cos\text{x}$
  1. Solution of given equation is:
  1. $\text{y}(1-\sin\text{x})=\text{x+c}$
  2. $\text{y}(1+\sin\text{x})=-\text{x}^2+\text{c}$
  3. $\text{y}(1-\sin\text{x})=\frac{\text{-x}^2}{2}\text{+c}$
  4. $\text{y}(1+\sin\text{x})=\frac{\text{-x}^2}{2}\text{+c}$
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  2. $\frac{2+\text{x}^2}{2(1+\sin\text{x})}$
  3. $\frac{2-\text{x}^2}{2(1-\sin\text{x})}$
  4. $\frac{2+\text{x}^2}{2(1-\sin\text{x})}$
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  1. $\frac{4-\pi^2}{2}$
  2. $\frac{8-\pi^2}{16}$
  3. $\frac{8-\pi^2}{4}$
  4. $\frac{4+\pi^2}{2}$
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  1. Probability of occurrence of event $E$ given that the balls drawn are from box I, is:
  1. $\frac{1}{9}$
  2. $\frac{2}{6}$
  3. $\frac{3}{5}$
  4. $\frac{1}{7}$
  1. Probability of occurrence of event $E$, given that the balls drawn are from box II, is:
  1. $\frac{1}{3}$
  2. $\frac{1}{4}$
  3. $\frac{3}{4}$
  4. $\frac{3}{5}$
  1. Probability of occurrence of event $E,$ given that balls drawn are from box III, is:
  1. $\frac{1}{12}$
  2. $\frac{3}{11}$
  3. $\frac{1}{6}$
  4. $\frac{4}{11}$
  1. The value of $\displaystyle{\sum^3_{\text{i}=1}}\text{P(E}|\text{E}_\text{i})$ is equal to.
  1. $\frac{5}{18}$
  2. $\frac{1}{2}$
  3. $\frac{1}{18}$
  4. $\frac{11}{18}$
  1. The probability that the balls drawn are from box II, given that event $E$ has already occurred, is:
  1. $\frac{1}{11}$
  2. $\frac{6}{11}$
  3. $\frac{5}{11}$
  4. None of these
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Three shopkeepers Ram Lal, Shyam Lal, and Ghansham are using polythene bags, handmade bags (prepared by prisoners), and newspaper's envelope as carry bags. It is found that the shopkeepers Ram Lal, Shyam Lal, and Ghansham are using (20, 30, 40), (30, 40, 20), and (40, 20, 30) polythene bags, handmade bags, and newspapers envelopes respectively. The shopkeepers Ram Lal, Shyam Lal, and Ghansham spent ₹250, ₹270, and ₹200 on these carry bags respectively.
  1. What is the cost of one polythene bag?
  1. ₹ 1
  2. ₹ 2
  3. ₹ 3
  4. ₹ 5
  1. What is the cost of one handmade bag?
  1. ₹1
  2. ₹2
  3. ₹3
  4. ₹5
  1. What is the cost of one newspaper bag?
  1. ₹1
  2. ₹2
  3. ₹3
  4. ₹5
  1. Keeping in mind the social conditions, which shopkeeper is better?
  1. Ram Lal
  2. Shyam Lal
  3. Ghansham
  4. None of these
  1. Keeping in mind the environmental conditions, which shopkeeper is better?
  1. Ram Lal
  2. Shyam Lal
  3. Ghansham
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