Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. Differential coefficient of {xl+mmn}1nl{xm+nnl}1lm{xn+llm}1mn with respect to x is:

NTA AbhyasNTA Abhyas 2022

Solution:

Let P = ({x(l+mmn)})1nl({x(m+nnl)})1lm({x(n+llm)})1mn
As (ab)c=abc , we get,
P={x((l+m)(mn)(nl))}{x((m+n)(nl)(lm))}{x((n+l)(lm)(mn))}
As (ab)(ac)=ab+c , we get,
P=x{(l+m)(mn)(nl)+(m+n)(nl)(lm)+(n+l)(lm)(mn)}
Solving the exponent of x we get,
(l+m)(mn)(nl)+(m+n)(nl)(lm)+(n+l)(lm)(mn)
=(l+m)(lm)+(m+n)(mn)+(n+l)(nl)(mn)(nl)(lm)
=(l2m2)+(m2n2)+(n2l2)(mn)(nl)(lm)
=0
Hence, P=x0 .
P=1
dPdx=ddx(1)
P(x)=0
Hence, the differential coefficient of P is 0 .