tolong dijwb no 15&16 pake caranya, mksh

Caranya di gambar yaa

15). y = (1-x)^2 x (2x+3)

Misalkan:
u = (1-x)^2 = 1 - 2x + x^2
v = (2x + 3)
u' = -2(1-x) = 2x - 2
v' = 2
Maka:
y' = u'.v + v'.u
= (2x-2)(2x+3) + 2(1-2x+x^2)
= 4x^2 + 6x - 4x - 6 + 2 - 4x + 2x^2
= 6x^2 - 2x - 4
= 3x^2 - x - 2
= (3x + 2 )(x - 1)
Jawaban C

16). f(x) = 3x^4 + ax^2 - 5
f'(1) = 4
f'(2)....?

f(x) = 3x^4 + ax^2 - 5
f'(x) = 12x^3 + 2ax
f'(1) = 12(1)^3 + 2a(1)
4 = 12 + 2a
2a = -8
a = -4

karena nilai a = -4, maka fungsi f'(x) menjadi
f'(x) = 12x^3 - 8x
Maka
f'(2) = 12(2)^3 - 8(2)
= 96 - 16
= 80
Jawaban B