Question
If y = 500e7x + 600e-7x show that $\frac{{{d^2}y}}{{d{x^2}}} = 49y$.

Answer

Given: y = 500e7x + 600e-7x ...(i)

$\therefore \frac{{dy}}{{dx}} $ = 500e7x(7) + 600e-7x(-7) = 500(7)e7x - 600(7)e-7x

$\Rightarrow \frac{{{d^2}y}}{{d{x^2}}} $ = 500(7)e7x(7) - 600(7)e-7x(-7) = 500(49)e7x + 600(49){e-7x

$\Rightarrow \frac{{{d^2}y}}{{d{x^2}}} $ = 49[500e7x + 600e-7x]

= 49y [From eq. (i)]

$\Rightarrow \frac{{{d^2}y}}{{d{x^2}}} = 49y$ Hence proved.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Find the maximum and the minimum values, if any, without using derivaives of the following functions:

f(x) = 2x+ 5 on R.

Evaluate the following integrals:
$\int\frac{\text{x}}{(\text{x}^2+1)\sqrt{\text{x}}}\text{ dx}$
Discuss the applicability of Lagrange's mean value theorem for the function:
f(x) = |x| on [−1, 1]
In a game, a man wins ₹ 5 for getting a number greater than 4 and loses ₹ 1 otherwise, when a fair die is thrown. The man decided to throw a die three but to quit as and when he gets a number greater than 4. Find the expected value of the amount he wins/loses.
The rate of growth of a population is proportional to the number present. If the population of a city doubled in the past 25 year, and the present population is 100000, when will the city have a population of 500000?
Show that the following system of linear equation is inconsistent:
4x − 5y − 2z = 2
5x − 4y + 2z = −2
2x + 2y + 8z = −1
A firm manufactures headache pills in two sizes A and B. Size A contains 2 grains of aspirin, 5 grains of bicarbonate and 1 grain of codeine; size B contains 1 grain of aspirin, 8 grains of bicarbonate and 66 grains of codeine. It has been found by users that it requires at least 12 grains of aspirin, 7.4 grains of bicarbonate and 24 grains of codeine for providing immediate effects. Determine graphically the least number of pills a patient should have to get immediate relief. Determine also the quantity of codeine consumed by patient
The slope of the tangent at a point P(x, y) on a curve is $\frac{-\text{x}}{\text{y}}$. If the curve passs es through the point (3, -4). Find the equation of the curve.
Five defective mangoes are acciedently mixed with 15 good ones. Four mangoes are drawn at random from this lot. Find the probability distribution of the number of defective mangoes.
Find the distance between the lines l1 and l2 given by

$\vec{\text{r}}=\hat{\text{i}}+2\hat{\text{j}}-4\hat{\text{k}}+\lambda\big(2\hat{\text{i}}+3\hat{\text{j}}+6\hat{\text{k}}\big)$ and, $\vec{\text{r}}=3\hat{\text{i}}+3\hat{\text{j}}-5\hat{\text{k}}+\mu\big(2\hat{\text{i}}+3\hat{\text{j}}+6\hat{\text{k}}\big)$