ISRO Scientist or Engineer Civil 2015
Instructions
For the following questions answer them individually
Question 72
The series $$1+\frac{1}{2^{2}}-\frac{1}{3^{2}}-\frac{1}{4^{2}}-\frac{1}{5^{2}}+\frac{1}{6^{2}}-\frac{1}{7^{2}}-\frac{1}{8^{2}}+............\infty$$ is
Question 73
The complete solution of the linear differential equation $$\frac{d^{2} y}{dx^{2}}+(a+b)\frac{dy}{dx}+aby=0$$
Question 76
The period of a simple pendulum is $$T = 2\pi \sqrt{\frac{L}{g}}$$.The maximum error in 7 due to the possible error upto 1% in ‘L’ and 2.5% in ‘g’ is
Question 78
If $$f(x, y) = x^{3}y - xy^{3}$$, then what is the value of $$[\frac{1}{(\frac{df}{dx})}+\frac{1}{(\frac{df}{dy})}] x = 1, y = 2 ?$$
Question 80
The solution of $$\frac{d^{2}z}{dx^{2}}+z = 0$$ given that when $$x = 0, z = e^{y}$$ and $$\frac{dz}{dx} = 1$$ is
