Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Continuity and Differentiability

Question:

If P(x) is a polynomial such that $P\left(x^2+1\right)=\{P(x)\}^2+1$ and P(0) = 0, then P'(0) is equal to

Options:

1

0

-1

none of these

Correct Answer:

1

Explanation:

We have,

$P\left(x^2+1\right)=\{P(x)\}^2+1$ for all x

$\Rightarrow P(x)=x$ for all x

Clearly, it also satisfies P(0) = 0

Now,

$P(x)=x \Rightarrow P'(x)=1$  for all  $x \Rightarrow P'(0)=1$