Question

2. Suatufungsi f(x) = 4x -1. F(a) = -9, dan f(2)= b. Nilai a - b adalah ....

Answer 1

a - b = -9

Penjelasan dengan langkah-langkah:

Diketahui:

f(x) = 4x - 1

f(a) = -9

f(2) = b

Ditanya:

a - b = ...?

penyelesaian:

f(x) = 4x - 1

f(a) = -9

4a - 1 = -9

4a = -9 + 1

4a = -8

a = [tex] \displaystyle\tt~ -\frac{8}{4} [/tex]

a = -2

f(2) = b

4(2) - 1 = b

8 - 1 = b

b = 7

a - b = -2 - 7 = -9