4x+41-x=4 হলে, x = কত?
A
14
B
13
C
12
D
1
Correct Answer: 12
4^x+4^1-x=4d/dx[4^x+4^1-x]=04^x.ln4-4^1-x.ln4=04^x.ln4=4^1-x.ln44^x=4^1-xX=1-x2x=1X=1/2