Question

Help plz!

Find the indefinite integral of 3x² + 4x given that when x = 1, the indefinite integral is -2.

Answer 1

y = x³ + 2x² - 5

Explanation:

using the power rule

• ∫a
`x^(n)` =
`(a)/(n+1)`
`x^(n+1)` → (n ≠ - 1 )

y = ∫(3x² + 4x ) dx

y = x³ + 2x² + c ( c is the constant of integration )

to find c use y = - 2 when x = 1

1 + 2 + c = - 2 ⇒ c = - 2 - 3 = - 5

y = x³ + 2x² - 5