Question

Diketahui f(x)=(x+a)+3dan f(2)=7
tentukan
a.bentuk fungsi f(x)
b. nilai f(-1)
c. nilai f(-2)+f(-1)
d. bentuk fungsi f(2x-5)

Answer 1

soal a
f(x) = (x + a) + 3
f(2) = (2 + a) + 3
7 = 2 + a + 3
7 = 5 + a
a = 7 - 5
a = 2

f(x) = (x + a) + 3
f(x) = (x + 2) + 3
f(x) = x + 2 + 3
f(x) = x + 5

soal b
f(-1) = -1 + 5
f(-1) = 4

soal c
f(-2) + f(-1) = (-2 + 5) + (- 1 + 5)
f(-2) + f(-1) = 3 + 4
f(-2) + f(-1) = 7

soal d
f(x) = x + 5
f(2x-5) = 2x-5 + 5
atau
f(2x-5) = 2x