Question

What is the net area between `f(x)=7x-8` in `x in[1,2]` and the x-axis?

Answer 1

`A = 5/2`

Explanation:

The area is given by:
`A = int_1^2 f(x) dx = int_1^2 (7x-8) dx`

`:. A = [ (7x^2)/2-8x ]_1^2dx`

`:. A = [ (7x^2)/2-8x ]_1^2dx`

`:. A = { ( ((7)(4))/2-16 ) - (((7)(1))/2 - 8) }`
`:. A = { (14-16 ) - (7/2 - 8) }`
`:. A = -2 - 7/2 + 8`
`:. A = 6 - 7/2`
`:. A = 5/2`