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What is f(g(x)) when f(x) = x ^ 2 + 5 , and g(x) = 10 - 5x ?

User Karli
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1 Answer

4 votes

A function f (x) and g (x) then:

(f + g) (x) = x² - x + 6

Further explanation

Like the number operations we do in real numbers, operations such as addition, installation, division or multiplication can also be done on two functions.

Suppose a function f (x) and g (x) then:

(f + g) (x) = f (x) + g (x)

(f + g) (x) is a new function of the sum of f (x) and g (x)

Likewise with other function operations:

(f-g) (x) = f (x) - g (x)

(fg) (x) = f (x) x g (x)

(f / g) (x) = f (x) / g (x)

In addition to the above operations we can combine two functions using the function composition with the symbol o

(fog) (x) = f ((g (x))

Known on the question

f (x) = x² + 1

g (x) = 5 x

Summing the two functions f (x) and g (x):

(f + g) (x) = f (x) + g (x)

(f + g) (x) = x² + 1 + 5 - x

(f + g) (x) = x² - x + 6

User Ayush Narula
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6.0k points