Respuesta :

Answer:

[tex](q \circ r)(7)=22[/tex]

[tex](r \circ q)(7)=8[/tex]

Step-by-step explanation:

1st problem:

[tex](q \circ r)(7)=q(r(7))[/tex]

r(7) means to replace x in [tex]\sqrt{x+9}[/tex] with 7.

[tex]r(7)=\sqrt{7+9}=\sqrt{16}=4[/tex]

[tex](q \circ r)(7)=q(r(7))=q(4)[/tex]

q(4) means replace x in [tex]x^2+6[/tex] with 4.

[tex]q(4)=4^2+6=16+6=22[/tex].

Therefore,

[tex](q \circ r)(7)=q(r(7))=q(4)=22[/tex]

2nd problem:

[tex](r \circ q)(7)=r(q(7))[/tex]

q(7) means replace x in [tex]x^2+6[/tex] with 7.

[tex]q(7)=7^2+6=49+6=55[/tex].

So now we have:

[tex](r \circ q)(7)=r(q(7))=r(55)[/tex].

r(55) means to replace x in [tex]\sqrt{x+9}[/tex] with 55.

[tex]r(55)=\sqrt{55+9}=\sqrt{64}=8[/tex]

Therefore,

[tex](r \circ q)(7)=r(q(7))=r(55)=8[/tex].