Differentiation Question 444

Question: If $ y={{(1+x)}^{x}}, $ then $ \frac{dy}{dx}= $

Options:

A) $ {{(1+x)}^{x}}[ \frac{x}{1+x}+\log ex ] $

B) $ \frac{x}{1+x}+\log (1+x) $

C) $ {{(1+x)}^{x}}[ \frac{x}{1+x}+\log (1+x) ] $

D) None of these

Show Answer

Answer:

Correct Answer: C

Solution:

$ y={{(1+x)}^{x}} $

Taking log on both sides, $ \log y=x\log (1+x) $

Differentiating w.r.t. x, we get $ \frac{1}{y}\frac{dy}{dx}=\log (1+x)+x\frac{1}{(1+x)} $

Thus $ \frac{dy}{dx}={{(1+x)}^{x}}[ \frac{x}{1+x}+\log (1+x) ] $