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If f(x)=2x+3 and g(x)=−f(x−1)+5, what is the value of
g(f(−1))?

User Sarreph
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1 Answer

4 votes

Final answer:

To find g(f(-1)), calculate f(-1) first, which is 1. Then, use f(-1) to evaluate g(1) which requires finding f(0) that equals to 3. Finally, compute g(f(-1)) as -3 + 5, resulting in 2.

Step-by-step explanation:

To find the value of g(f(-1)), we first need to determine the output of f(-1). Then substitute this output into the function g(x).

Step 1: Calculate f(-1). Using the definition of the function f(x) = 2x + 3, substitute -1 for x:

f(-1) = 2(-1) + 3 = -2 + 3 = 1.

Step 2: Find g(f(-1)). According to the function definition, g(x) = -f(x - 1) + 5, substitute f(-1) which we determined to be 1 into this function:

g(1) = -f(1 - 1) + 5 = -f(0) + 5.

Step 3: Now compute f(0). Again using the formula for f(x):

f(0) = 2(0) + 3 = 3.

Step 4: Combine these results to evaluate g(f(-1)):

g(f(-1)) = g(1) = -f(0) + 5 = -(3) + 5 = -3 + 5 = 2.

Therefore, the value of g(f(-1)) is 2.

User Firemaples
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