Question

Jika (3x - 5)^4 = ((3x - 5)^2)^2 = ax^4 + bx^3 + cx^2 + dx + e, maka nilai a+b+c+d+e = ???
mohon diuraikan dan jawaban nya. terima kasih

Answer 1

(3x-5)^4 = (3x-5) (3x-5) (3x-5) (3x-5)
= (9x^2 - 30x + 25) (9x^2 - 30x + 25)
= 81x^4 - 270x^3 + 225x^2 - 270x^3 + 900x^2 - 750x + 225x^2 - 750x + 625
= 81x^4 - 540x^3 + 1350x^2 - 1500x + 625

a = 81
b = -540
c = 1350
d = -1500
e = 625
a + b + c + d + e = 81 - 540 + 1350 - 1500 + 625
= 16