Question

The derivative of $x^2+3x-2tan\left(x\right)$ will be equal to

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

If you see that the given question has three functions
(i) $x^2$ (ii) 3x (iii) 2 tan x
First two are being added and third one is being subtracted from the second one. So as per the addition / subtraction rule for derivatives, we will find the derivatives of $x^2,3xand2tanx$ and add the first two derivatives and subtract the third from the first two.
So
Derivative of $x^2=2x$
Derivative of 3x = 3
Derivative of $2tanx=2se{c}^{2}x$
So $\frac{d}{dx}(x^2+3x-2tanx)=2x+3-2se{c}^{2}x$