Question

F(x) = { 2x - 1, untuk 0 < x < 1
{ x² + 1, untuk x yang lain
tentukan f(2).f(-4)+f(1/3).f(3)

Answer 1

F(2).f(-4) + f(1/3).f(3)
= (2² + 1)((-4)² + 1) + (2(1/3) - 1)(3² + 1)
= 5(17) + (-1/3)(10)
= 85 - 10/3
= 255/3 - 10/3
= 245/3

Answer 2

F(x) = 2x-1 untuk 0 < x < 1
f(x) = x²+1 untuk x yang lain

f(2) = 2²+1 = 4+1 = 5
f(-4) = (-4)²+1 = 16+1 = 17
f(1/3) = 2(1/3)-1 = 2/3-1 = -1/3
f(3) = 3²+1 = 9+1 = 10

f(2).f(-4)+f(1/3).f(3) = 5.17+(-1/3.10)
                           = 85-10/3
                           = 245/3
                           = 81 2/3