Math miscellaneousHard

Question

Ifex2 (x - α)dx = 0, then

Options

A.1 < α < 2
B.α < 0
C.0 < α < 1
D.α = 0

Solution

Ifex2(x - α)dx = 0, then ex2.x dx = ex2 a dx
(e  -  1)  =  αex2dx
ex2 is an increasing function 0 ≤ x ≤ 1 therefore 1≤ ex2≤ e when 0 ≤ x ≤ 1
1(1-0) ≤ex2dx ≤ e(1 - 0) ⇒ 1 ≤ ex2dx ≤ e
equation (1) and (2) . we find that L.H.S. of equation is +ve and ex2dx lies between 1 & e. Therefore a is a positive real no.
α = The denominator of equation is greater than unity and numerator lies between 0 and 1.

Create a free account to view solution

View Solution Free
Topic: Math miscellaneous·Practice all Math miscellaneous questions

More Math miscellaneous Questions