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Can anyone help me with these three plz ??? I have no clue how to do this

Can anyone help me with these three plz ??? I have no clue how to do this-example-1
User Ilkin
by
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1 Answer

5 votes

Answer for question (42):

We need to find the composition of two functions f(x) and g(x).

By the definition, the composition of two functions
f\circ g(x) is defined as
f(g(x)).

That is, The composition of two functions f and g is the new function , by performing g first and then performing f.

Here we have
f(x)=3x^3, g(x)=x-1


f\circ g(x)=f[g(x)]

Now plug in
g(x)=x-1, we get


f\circ g(x)=f[g(x)]=f(x-1)

It is given that
f(x)=x^3, using this we need to find
f(x-1).

Replace x by x-1 in f(x),


f[g(x)]=f(x-1)=3(x-1)^3

Now we need to find
f(g(3)),


f[g(3)]=3(3-1)^3=3(2^3)=3*8=24

So
f(g(3)=24

So the soiution is (B): 24

Solution for question (43):


h(x)=6x^2+5x-13

Plug in
x=-5, to find h(-5):


h(-5)=6*(-5)^2+5*(-5)-13


=6*25+5*-5-13\\ =112+5(-5)-13 [/tex]

Thus the answer for (43) is (D): 112.

Solution for question (44):

The height of a ball projected into the air can be represented by the function is


h(t)=-16t^2+64t

Then to find the height of the ball in feet when it has been in the air for 2 seconds:

Plug in t=2 in h(t),


h(2)=-16*2^2+64*2


image


=64

Thus the answer for (44) is (A): 64.

User Nik Klassen
by
5.0k points
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