20. [tex] f : R \rightarrow R, f(x) = ax+b[/tex]
a)0a + b = 2
b = 2
a + b = 2
a + 2 = 2
a = 0
f(x) = 2
b)-2a + b = 0
b = 2a
0a + b = 2
2 = 2a
a = 1
f(x) = x + 2
c)-a + b = -2
a = b+2
2a + b = 5
2(b+2) + b = 5
2b + 4 + b = 5
3b = 1
b = 1/3
a = 1/3 + 2
a = 7/3
f(x) = 7x/3 + 1/3
19.[tex] f : R \rightarrow R, f(x) = ax+b[/tex]
a + b = 3
-2a + b = 0
b = 2a
a + 2a = 3
3a = 3
a = 1
b = 2
f(x) = x + 2
