# math

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Given that g(x)= 2x+1/5 and f(x)=x+4

Calculate the value of g(-2)
2(-2)+1/5= -3/5
Is this right??

How do i write an expression for gf(x) in the simpliest form??

And how do i find inverse functions such as g`1(x)?

• math -

g(x) = 2x+1/5
Substitute -2 for x.

g(-2) = 2*-2 + 1/5
g(-2) = -4 + 1/5
g(-2) = (-3 4/5) (mixed number)

To find g(f(x)), substitute f(x) for x in g.

g(f(x)) = g(x+4)
g(x+4) = 2(x+4) + 1/5
g(x+4) = 2x + 8 + 1/5
g(x+4) = 2x + (8 1/5) (mixed number)

To find inverse functions, switch the y and x.

convert g(x) = 2x+1/5 to y = 2x+1/5
Now switch y and x.
x = 2y+1/5

solve for y
x-1/5 = 2y
x/2 - 1/10 = y
g'1(x) = x/2 - 1/10

• math -

for the #1 how do u got -3 4/5 if u check good u got -3/5

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