Differentiation Question 45
Question: If $ y=(1+{x^{1/4}})(1+{x^{1/2}})(1-{x^{1/4}}) $ , then $ \frac{dy}{dx} $ =
[MP PET 1994]
Options:
A) 1
B) - 1
C) x
D) $ \sqrt{x} $
Show Answer
Answer:
Correct Answer: B
Solution:
$ y=(1+{x^{1/4}})(1+{x^{1/2}})(1-{x^{1/4}}) $
Therefore $ y=(1+{x^{1/4}})(1-{x^{1/4}})(1+{x^{1/2}}) $
$ =(1-{x^{1/2}})(1+{x^{1/2}})=1-x\Rightarrow \frac{dy}{dx}=-1 $ .
BETA
