How do you evaluate the definite integral int (2x-3) dx from [1,3]?

1 Answer
Mar 12, 2018

2

Explanation:

Given: int(2x-3)dx from [1,3]

int_1^3(2x-3)dx =int_1^3(2x)dx - int_1^3 3 dx

Use: int(kx^n)dx = k*1/(n+1)x^(n+1) + C

int_1^3(2x)dx - int_1^3 3 dx = 2*1/2 x^2 - 3x |_1^3

= x^2 - 3x |_1^3 = (3^2 - 3*3) - (1^2 - 3*1)

= (9-9) - (1-3) = 0 -(-2)

= 2