Question

dada a função f(x)=x²-3x-4 calcule:
a) f(-2)
b) f(5)
c) f(3/2)

Answer 1

f(x) = x² - 3x - 4

a) f(-2)

f(-2) = (-2)² - 3(-2) - 4

f(-2) = 4 + 6 - 4

f(-2) = 10 - 4

f(-2) = 6

b) f(5)

f(5) = (5)² - 3(5) - 4

f(5) = 25 - 15 - 4

f(5) = 25 - 19

f(5) = 6

c) f(3/2)

f(3/2) = (3/2)² - 3(3/2) - 4

f(3/2) = 9/4 - 9/2 - 4

f(3/2) = 9/4 - 18/4 - 16/4

f(3/2) = 9/4 - 34/4

f(3/2) = - 25/4