No. Date: 1. Jika f (x) = 2x-1 dan (fog) (x) = -4x+21, nilai dari g(-3) 2. Jika f(x) = 5x+2 dan g(x) = x², nilai (fog) (2) = ... 3 Jika f(x) = 3x+7 dan g(x) = 6 (fog) (2) H. Jika f(x) (-9) Pasangan a. 32 6.22 C16 " H x = 0, nilai = 2x+3 dan g(x) =9-x, nilai dari (fog) d. 15 e.13 -1
Answer (1)
Jawaban: 1. Nilai g(-3) jika f(x) = 2x - 1 dan (f o g)(x) = -4x + 21 - (f o g)(x) = f(g(x)) = 2g(x) - 1 = -4x + 21- 2g(x) = -4x + 22- g(x) = -2x + 11- g(-3) = -2(-3) + 11 = 6 + 11 = 17 2. Nilai (f o g)(2) jika f(x) = 5x + 2 dan g(x) = x² - (f o g)(x) = f(g(x)) = 5(x²) + 2- (f o g)(2) = 5(2²) + 2 = 5(4) + 2 = 20 + 2 = 22 3. Nilai (f o g)(2) jika f(x) = 3x + 7 dan g(x) = 6 - Karena g(x) = 6 (konstan), maka g(2) = 6- (f o g)(2) = f(g(2)) = f(6) = 3(6) + 7 = 18 + 7 = 25 4. Nilai x jika f(x) = 2x + 3 dan g(x) = 9 - x, dan (f o g)(x) = -1 - (f o g)(x) = f(g(x)) = 2(9 - x) + 3- 2(9 - x) + 3 = -1- 18 - 2x + 3 = -1- 21 - 2x = -1- -2x = -22- x = 11 Kesimpulan: 1. g(-3) = 172. (f o g)(2) = 223. (f o g)(2) = 254. x = 11
