Question

Diket rumus fungsi f(x) x^2 + 3x - 5
tentukan daerah hasil fungsi f.

Answer 1

X² + 3x - 5
a = 1
b = 3
c = -5

D = b² -4ac
D = 3² - 4.1.-5
D = 9 + 20
D = 29

x1 = -b + √D / 2a
= -3 + √29 / 2

x2 = -b - √D / 2a
= -3 - √29 / 2

daerah hasil = subtitusi dengan x1 dan x2

daerah hasil x1 = (-3 + √29 / 2)² + 3(-3 + √29 / 2) - 5
= 9 + 29 / 4 + ((-9) + 3√29) / 2 - 5
= 38/4 - 9/2 + 3√29/2 - 10/2
= 19/2 - 9/2 + 3√29/2 - 10/2
= 3√29/2

daerah hasil x2 = (-3 - √29 / 2)² + 3(-3 - √29 / 2) - 5
= 9 + 29/4 + (-9 - 3√29/2) - 5
= 38/4 - 9/2 - 3√29/2 - 10/2
= 19/2 - 9/2 - 3√29/2 - 10/2
= - 3√29/2

jadi daeraj hasil :

3√29/2 atau -3√29/2