Question

Tolong bantu aku ya diketahui f(xkuadrat - 2) = 6x + 5 dan g \frac{2x-1}{4x+3} = 3x - 2 tentukan
a. f(x) dan g(x)
b. (f+g)(2)
c. (f×g)(-1)

Answer 1

F(x² - 2) = 6x - 5
misal y = x²-2
x²= y+2
x= √(y+2)
f(y) = 6√(y+2) - 5
f(x) = 6√(x+2) - 5

g{(2x-1)(4x+3)} = 3x-2
misal y = 8x² + 2x -3
8x²+2x = y+3
x² + 1/4x = 1/8(y+3)
(x + 1/2)² =1/8y + 3/8 + 1/4= 1/8y + 5/8= 1/8 (y+5)
x+ 1/2 = √{ 1/8 (y+5)}
x = -1/2 +√{1/8(y+5)
x = -1/2 + 1/4 √(2y+10)}
g(x) = 3 [ -1/2 +1/4 √{2x+10)]
g(x) = 3/4 [ -2 + √(2x+10)}
..
b) f+g(2) = 6√4 - 5 + 3/4[-2+√14) = 7- 3/2 + 3/4√14= 11/2 + 3/4√14
c. f.g(-1) = [6√1 -5 ] [ 3/4 (-2 +√8)]
f.g(-1) = 1( -3/2 + 3/2√2)
f.g(-1) = 3/2( 1+√2)
..