Most Important Selected Qs for JEE AdvancedMathematicsContinuity and Differentiability
Paragraph: Let f be a differentiable function satisfying [3] f(x+y) = [3] f(x) + [3] f(y) +1 x, y R and f^ (0)=3 Question: If h(x)=f(x)-x^3 , then number of point(s) where y=h(|x|) is non-derivable is(are):
Options
- A0
- B1
- C2
- D3
Correct answer
B. 1
Step-by-step solution
aligned & f(x)=(x-1)^3 & f(x)-x^3=-3 x^2+3 x-1=h(x) aligned (i) Clearly, y=h(|x|) is non-derivable at exactly one point. (ii) f(x) and f⁻¹(x) meet on the line y=x at x=x₀ where 2 ⁻¹ ( 2 x₀ )+4 ⁻¹ ( x₀ 2 )= (2 -2 x₀ )+4 x₀ 2 =2