15-17 ︎ ︎ ︎ ︎ ︎ ︎ ︎ ︎ ︎
15) f(x) = -x -1
masukkan x=1
f(1) = -1-1= –2
diperoleh (1,-2)
masukkan x=2
f(2)= -2-1 = –3
diperoleh (2,-3)
jadi, gambar B adalah jawaban benar.
16) f(x)= -½x +1
5 = -½ a +1
5-1 = -½ a
4(-2) = a
a = -8
17) f(x) = -½x+5
f(4)= -2+5= 3
f(6)= -3+5= 2
——-_
1
jadi, f(4)-f(6)= 1
________
semangat belajar…..