How do you evaluate the definite integral int 4x-54x5 from [1,2][1,2]?

1 Answer
Sep 11, 2016

11.

Explanation:

Recall the Fundamental Principle of Definite Integration :

if intf(x)dx=F(x)+C, then, int_a^bf(x)dx=F(b)-F(a)=[F(x)]_a^b.

int(4x-5)dx=4x^2/2-5x+C=2x^2-5x+C

:. int_1^2(4x-5)dx=[2x^2-5x]_1^2=[(8-10)-(2-5)]=-2+3=1.