Tolong dikerjakan nomor 4 dan 5! #DenganLangkahCara #SpamLangsngHapus Terima Kasih ^_^

Kelas 8 Matematika
Bab Fungsi

4] f(x) = 2x² - 1
f(x + 1) = f(x - 1)
2(x + 1)² - 1 = 2 (x - 1)² - 1

◎◎ coret (-1) dan 2 ◎◎

x² + 2x + 1 = x² - 2x + 1
x² - x² + 2x + 2x = 1 - 1
4x = 0
x = 0

5] f(x) = -4x² + 2
f(x + 2) = f (x - 2)
-4(x + 2)² + 2 = -4(x - 2)² + 2

◎◎ coret (-4) dan (+2) di luar kurung ◎◎

x² + 4x + 4 = x² - 4x + 4
x² - x² + 4x + 4x = 4 - 4
8x = 0
x = 0

Soal No. 4

[tex]f(x) = 2x^2-1 \\ \\ Jika\ f(x+1)=f(x-1)\ \to x=? \\ \\ 2(x+1)^2-1=2(x-1)^2-1 \\ 2(x^2+2x+1)-1=2(x^2-2x+1)-1 \\ 2x^2+4x+2-1=2x^2-4x+2-1 \\ 2x^2+4x+1=2x^2-4x+1 \\ (2x^2-2x^2)+(4x+4x)+(1-1)=0 \\ 8x=0 \\ x=0[/tex]

Soal No. 5

[tex]f(x) = -4x^2+2 \\ \\ Jika\ f(x+2)=f(x-2)\ \to x=? \\ \\ (-4)(x+2)^2+2=(-4)(x-2)^2+2 \\ (-4)(x^2+4x+4)+2=(-4)(x^2-4x+4)+2 \\ -4x^2-16x-16+2=-4x^2+16x-16+2 \\ -4x^2-16x-14=-4x^2+16x-14 \\ (-4x^2+4x^2)-(16x+16x)-(14-14)=0 \\ (-32x)=0 \\ x=0[/tex]

***Semoga Terbantu***