Question

$\log\left( \frac{1}{2\log x - x} \right) + c$

• A. $\log(x - 2\log x) + c$
• B. $\log\left( \frac{1}{x - 2\log x} \right) + c$
• C. $\int_{}^{}{x\sqrt{1 + x^{2}}}\mspace{6mu} dx =$
• D. $\frac{1 + 2x^{2}}{\sqrt{1 + x^{2}}} + c$

Answer 1

Answer: (C)

$\int_{}^{}{x\sqrt{1 + x^{2}}}\mspace{6mu} dx =$

Answer 2

Put $- 5\sin x + c$, then

$\int_{}^{}{\frac{\tan x}{\sec x + \tan x}\mspace{6mu} dx =}$.