Given f, left bracket, x, right bracket, equals, minus, x, squared, plus, x, minus, 17f(x)=−x
2
+x−17, find f, left bracket, minus, 8, right bracketf(−8)
minus, left bracket, minus, 8, right bracket, squared, plus, left bracket, minus, 8, right bracket, minus, 17
To find f(-8), we substitute x=-8 into the function f(x)=-x^2+x-17:
f(-8) = -(-8)^2 + (-8) - 17
Simplifying this expression:
f(-8) = -64 + (-8) - 17
= -64 - 8 - 17
= -89
Therefore, f(-8) = -89.
Given f, left bracket, x, right bracket, equals, minus, x, squared, minus, 8, x, plus, 8f(x)=−x
2
−8x+8, find f, left bracket, minus, 5, right bracketf(−5)
To find f(-5), we substitute x=-5 into the function f(x)=-x^2-8x+8:
f(-5) = -(-5)^2 - 8(-5) + 8
Simplifying this expression:
f(-5) = -25 + 40 + 8
= 23
Therefore, f(-5) = 23.
To find the value of f(-8) using the given function, we substitute -8 into the function expression for x.
Step 1: Write down the function expression: f(x) = -x^2 + x - 17
Step 2: Substitute -8 for x in the function expression:
f(-8) = -(-8)^2 + (-8) - 17
Step 3: Simplify the expression inside the parentheses:
f(-8) = -64 + (-8) - 17
Step 4: Perform the addition and subtraction operations:
f(-8) = -64 - 8 - 17
f(-8) = -89
Therefore, f(-8) = -89.