jawabin soal nomor 11 nya dong

2
integral (ax^2 - 6x + 5)dx =15
-1

2
...[(a/3)x^3 - 3x^2 + 5x] = 15
-1

[(a/3)(2)^3 - 3(2)^2 + 5(2)] - [(a/3)(-1)^3 - 3(-1)^2 + 5(-1)] = 15

[(8a)/3 - 12 + 10 - ((-a/3) - 3 - 5)] = 15
[(8a)/3 - 12 + 10 + (a/3) + 3 + 5] = 15
(9a/3) + 6 = 15
3a + 6 = 15
3a = 15 - 6
3a = 9
a = 9/3
a = 3

jadi besarnya a adalah 3 (C)