Question
Question: If y = (1 + x) (1 + x<sup>2</sup>) (1 + x<sup>4</sup>) …. (1 + x<sup>2n</sup>), then \(\frac{dy}{dx}...
If y = (1 + x) (1 + x2) (1 + x4) …. (1 + x2n), then dxdy at x = 0 is
A
1
B
– 1
C
0
D
None of these
Answer
1
Explanation
Solution
y = (1−x)(1−x) (1 + x2)….(1 + x2n) = 1−x1−(x2n)2
dxdy=(1−x)2(1−x)(0−4n4n−1)−(1−x2n)(−1) ; at x = 0 ⇒ 1