If p and q are respectively the global maximum and global minimum of the function f ( x ) = x 2 e 2 x on the…

If p and q are respectively the global maximum and global minimum of the function f(x)=x2e2x on the interval [-2,2], then pe-4+qe4=
  1. 0
  2. 4e8
  3. 4
  4. 4e8+1

Solution

It is given that,

f(x)=x2e2x

Differentiating the above equation we get,

f'(x)=2e2xx2+2xe2x

0=2e2xx2+x

x2+x=0

x=0, -1

The maxima and minima is obtained at -2, -1, 0, 2 as the
function bound.

Thus,

f(-2)=(-2)2e-4=4e-4

f(-1)=(1)2e-2

f(0)=0

f(2)=(2)2e4=4e4

Thus, p=4e4 and q=0.

pe-4+qe4=4e4e-4+0=4e0=4

Asked in: AP EAMCET 2019 (21 Apr Shift 2)

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