If (2x+3) is a factor of 4x^4+ax^2+2x+3, find the value of a

Answer 1

Plug in x = -3/2 and solve for a
a = -9
4x^4+ax^2+2x+3 = (2x+3)(2x^3-3x^2+1)

Answer 2

sorry.
4x^4-9x^2+2x+3 = (2x+3)(2x^3-3x^2+1)