Get Answers to all your Questions

header-bg qa

Explain solution RD Sharma class 12 chapter Differentiation exercise 10.5 question 18 sub question (vii) maths

Answers (1)

Answer:   (\log (\cos x)-\tan x \cdot x) \cos x^{2}+\left[\frac{\cot x}{2}-\log \frac{\sin x}{x^{2}}\right](\sin x)^{\frac{1}{2}}

Given: (\cos x)^{x}+(\sin x)^{\frac{1}{x}}

Solution:  y=(\cos x)^{x}+(\sin x)^{\frac{1}{x}}
                    =u+v

                \begin{aligned} &u=(\cos x)^{x} \text { and } \\\\ &v=(\sin x)^{\frac{1}{x}} \end{aligned}

                \begin{aligned} &\ln (u)=x \ln (\cos x) \\\\ &\frac{1}{u} \frac{d u}{d x}=1 . \ln \left(\cos x+x \cdot \frac{1}{\cos x}(-\sin x)\right) \end{aligned}

                \frac{d u}{d x}=(\cos x)^{x}(\ln \cos x-x \tan x)        ...........(1)

                \begin{aligned} &\log v=\frac{1}{x} \ln \left(\sin x^{}\right) \mid \\\\ &\frac{1}{v} \frac{d v}{d x}=\frac{-1}{x^{2}} \log \left(\sin x+\frac{1}{x} \cdot \cos x\right) \end{aligned}

                \begin{aligned} \frac{d v}{d x} &=\frac{(\sin x)^{\frac{1}{x}}}{x^{2}}[x \cot x-\log (\sin x)] \\\\ y &=u+v \end{aligned}

                \frac{d y}{d x}=\frac{d u}{d x}+\frac{d v}{d x}

                \frac{d y}{d x}=(\log (\cos x)-x \tan x) \cos x^{2}+\left[\frac{\cot x}{2}-\log \frac{\sin x}{x^{2}}\right](\sin x)^{\frac{1}{x}}

 

Posted by

infoexpert26

View full answer