Suatu fungsi f dirumuskan dengan f(x)=px+q.jika f(2)=5 dan f(-2)=-11 rumus fungsi f(x)=adalah??

Diketahui :

– f(x) = px + q

– f(2) = 5

– f(- 2) = – 11

Ditanya :

– f(x) = ……?

Penyelesaian :

– Nilai p :

f(x) = px + q

f(2) = 2p + q

f(- 2) = – 2p + q

2p + q = 5

– 2p + q = – 11

———————— —

4p = 16

p = 16/4

p = 4

– Nilai q :

2p + q = 5

2(4) + q = 5

q = 5 – 8

q = – 3

– f(x) :

f(x) = px + q

f(x) = 4x + (- 3)

f(x) = 4x – 3

Jawaban:

2p + q = 5 .. (1)

-2p + q = -11 …(2)

——————-'–'—– –

4p = 16

p = 4

substitusi

2(4) + q = 5

q = 5-8

q = -3

rumus fungsibya = 4x -3