Diketahui fungsi f(x)=px+q,f(2)=5,f(3)=8,dan pernyataan: (i) f(7)=21 (ii) f(6)=19 (iii) f(5)=14 (iv) f(4)=11 pernyataan di atas yg bnar adalah... A. (i) dan (ii

f(2) = p.2+q = 5
f(3) = p.3+q = 8
2p+q = 5
3p+q = 8 dikurangkan
-p= -3
p= 3
2p+q = 5
2(3)+q = 5
6+q = 5
q = 5-6
q = -1

f(7)= 21
f(7) = 3(7)+(-1)
f(7) = 21-1 = 20 = > salah
f(6) = 19
f(6) = 3(6)+(-1)
f(6) = 18-1 = 17 => salah
f(5) = 14
f(5)= 3(5)+(-1)
f(5) = 15-1 = 14 => benar
f(4) = 11
f(4) = 3(4)+(-1)
f(4) = 12-1 = 11 => benar
jadi yg benar adalah iii dan iv