1.dik: rumus f(x+7)=2x-5.tentukan rumus f(x) 2.jika f(2x-3)=10x-9,maka rumus f(x)adlh 3.dik: rumus f(x)=ax+b.jika f(2)=-2 dan f(-3)=13 maka nilai dr a+b

1). f(x + 7) = 2x - 5
f(x) = 2(x - 7) - 5
f(x) = 2x - 14 - 5
f(x) = 2x - 19
2). f(2x - 3) = 10x - 9
f(x) = 10(x + 3)/2 - 9
f(x) = 5x + 15 - 9
f(x) = 5x + 6
3). f(2) = 2a + b = -2
f(-3) = -3a + b = 13
__________-
5a = -15
a = -15/5
a = -3
2a + b = -2
2(-3) + b = -2
-6 + b = -2
b = 6 - 2
b = 4
Nilai a + b = -3 + 4 = 1
4). f(x) = 3x + 4
f(4) = a => 3(4) + 4 = a
=> 12 + 4 = a
=> 16 = a
f(b) = -5
f(b) = 3b + 4 = -5
3b = -5 - 4
3b = -9
b = -9/3
b = -3

Nilai a+b = 16 + (-3) = 13

fungsi  komposisi
1. f(x+7)= 2x - 5
f(x)= 2(x-7) - 5
f(x)= 2x -14 -5
f(x)= 2x - 19

2. f(2x-3) = 10x - 9
f(x)= 10(x + 3)/2  - 9
f(x)= 5(x+3) - 9
f(x)= 5x +15 -9
f(x)= 5x + 6

3. f(X)= ax+b
f(2)=  - 2
f(-3) = 13
...
2a - (-3a)= -2 - 13
5a= -15
a = - 3

b = - 2 - 2a
b = -2 -2(-3)
b = -2+ 6  = 4

a + b = -3 + 4
a + b = 1

4. f(x) =3x + 4
f(4)= a --> 3(4)+ 4 = a
12+4 = a --> a = 16

f(b) =-5 --> 3b + 4 = - 5
3b = - 5-4 = - 9
b = -9 /3
b = - 3

a + b = 16 + (-3) 
a + b = 13