NTA Abhyas 2020
- Exam
- NTA Abhyas
- Year
- 2020
- Subject
- Mathematics
- Chapter
- Differentiation
NTA Abhyas 2020 · Mathematics · Differentiation
If f (x) is a twice differentiable function such that f^ " (x) = -...
If f^{"}\left(x\right) = - f\left(x\right) = g \left(x\right)\left(x\right)\left(10\right) = 10, is equal to
Options
- A
- B
- C
- D
Correct answer
C.
Step-by-step solution
\left(x\right) = 2f ⋅ f^{'} + 2gg^{'}= 2f ⋅ f^{'} + 2\left(f^{'}\right)\left(f^{"}\right) ( ∵ g = f^{'} )= 2f ⋅ f^{'} + 2f^{'} \left(-f\right) = 0∴ h^{'}\left(x\right) = 0 ⇒ h\left(x\right)∴ h\left(x\right) = 10 ⇒ h\left(5\right) = 10