Skip to main contentSkip to solution

If ddx(f(x))=5x4−4x5\frac{d}{dx}(f(x)) = 5x^4 - \frac{4}{x^5} such that f(1)=0f(1) = 0. Then f(2)−2f(12)f(2) - 2f\left(\frac{1}{2}\right) is equal to :

Solution

✅ Correct Option: 2

Integrating: f(x)=x5+1x4+Cf(x) = x^5 + \frac{1}{x^4} + C.

Using f(1)=0f(1) = 0: 1+1+C=0⇒C=−21 + 1 + C = 0 \Rightarrow C = -2.

So f(x)=x5+1x4−2f(x) = x^5 + \frac{1}{x^4} - 2.

f(2)=32+116−2=30+116f(2) = 32 + \frac{1}{16} - 2 = 30 + \frac{1}{16}.

f(1/2)=132+16−2=14+132f(1/2) = \frac{1}{32} + 16 - 2 = 14 + \frac{1}{32}.

f(2)−2f(1/2)=30+116−28−116=2f(2) - 2f(1/2) = 30 + \frac{1}{16} - 28 - \frac{1}{16} = 2.

Keyboard Shortcuts

  • Left arrow: Previous question
  • Right arrow: Next question
  • S key: Jump to solution
  • Q key: Jump to question