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If g(x)=x²x+1 and (gof)x=4x²-10x+5 then f(5/4) is equal to

User Lloiacono
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Final answer:

To find f(5/4), substitute g(x) into the equation (gof)x = 4x² - 10x + 5 and solve for f(5/4). The solution is f(5/4) = -5.

Step-by-step explanation:

To find f(5/4), we need to solve for f(x) in the equation (gof)x = 4x² - 10x + 5.

Substitute g(x) into the equation:

(x²x+1)(f(x)) = 4x² - 10x + 5

Expand and simplify:

x²(f(x)) + (f(x)) = 4x² - 10x + 5

Using the identity property of multiplication, we know that x²(f(x)) = x²f(x). Rewriting the equation, we get:

x²f(x) + f(x) = 4x² - 10x + 5

Factor out f(x) from both terms:

f(x)(x² + 1) = 4x² - 10x + 5

Now, substitute x = 5/4 and solve for f(5/4):

f(5/4)(5/4² + 1) = 4(5/4)² - 10(5/4) + 5

f(5/4)(25/16 + 1) = 4(25/16) - 10(5/4) + 5

f(5/4)(25/16 + 16/16) = 4(25/16) - 10(5/4) + 5

f(5/4)(41/16) = 25/4 - 50/4 + 5

f(5/4)(41/16) = -20/4 + 5

f(5/4)(41/16) = -5

Therefore, f(5/4) = -5.

User Nick Litwin
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