Test Index

CBSE Class 12 Maths 2010 Solved Paper

© examsnet.com
Question : 11 of 29
Marks: +1, -0
Find all points of discontinuity of f, where f is defined as following:
f (x) =
{x+3,x32x,3<x<36x+2,x3\begin{cases} x + 3, & x \le -3 \\ -2x, & -3 < x < 3 \\ 6x+2, & x \ge 3 \end{cases}
OR
Find dydx\frac{dy}{dx} , if y = (cosx)x+(sinx)1x(\cos x)^x + (\sin x)^{\frac{1}{x}}
Solution:  
Here, f (x) =
{x+3,x32x,3<x<36x+2,x3\begin{cases} x + 3, & x \le -3 \\ -2x, & -3 < x < 3 \\ 6x+2, & x \ge 3 \end{cases}
The function is defined on all the points and hence continuous possible points ofdiscontinuity are 3 and -3 . We need to check the continuity of the function at twopoints x = 3 and x = -3.
Case 1: For x = -3, f(-3) = -(-3) + 3 = 6
LHL = lim
© examsnet.com
Go to Question: