AP EAMCET2005MathematicsDifferentiation
If f(x)=10 x+(13+2 x) x, then f^ (x)+f(x) is equal to
Options
- Ax
- B4 x
- Cx
- D4 x
Correct answer
B. 4 x
Step-by-step solution
Given that On differentiating w.r.t. x , we get f^ (x)=-10 x+(13+2 x) x+2 x Again differentiating, we get aligned f^ (x)=-10 x-(13+2 x) x+ & 2 x & +2 x ...(ii) aligned On adding Eqs. (i) and (ii), we get f^ (x)+f(x)=2 x+2 x=4 x