Given the functions:
[tex]\[
\begin{array}{l}
d(x)=\sqrt{x+5} \\
m(x)=5x-3 \\
a(x)=x+2 \\
c(x)=5x^2+17x-12
\end{array}
\][/tex]

Find and simplify:
a. [tex]\((d \circ a)(x)\)[/tex]

b. [tex]\((d \circ a)(2)\)[/tex]

c. [tex]\((c \circ m)(x)\)[/tex]

d. [tex]\((m \circ c)(x)\)[/tex]



Answer :

Sure, let’s go through each part step-by-step.

Given functions:
[tex]\[ d(x) = \sqrt{x+5} \][/tex]
[tex]\[ m(x) = 5x - 3 \][/tex]
[tex]\[ a(x) = x + 2 \][/tex]
[tex]\[ c(x) = 5x^2 + 17x - 12 \][/tex]

We are to find and simplify the compositions:

### a. [tex]\((d \circ a)(x) = d(a(x))\)[/tex]

First, we need to substitute [tex]\( a(x) \)[/tex] into [tex]\( d(x) \)[/tex]:
[tex]\[ a(x) = x + 2 \][/tex]

Next, substitute [tex]\( a(x) \)[/tex] into [tex]\( d(x) \)[/tex]:
[tex]\[ d(a(x)) = d(x + 2) = \sqrt{(x + 2) + 5} \][/tex]

Simplify the expression inside the square root:
[tex]\[ \sqrt{x + 2 + 5} = \sqrt{x + 7} \][/tex]

So:
[tex]\[ (d \circ a)(x) = \sqrt{x + 7} \][/tex]

### b. [tex]\((d \circ a)(2) = d(a(2))\)[/tex]

First, find [tex]\( a(2) \)[/tex]:
[tex]\[ a(2) = 2 + 2 = 4 \][/tex]

Next, substitute [tex]\( 4 \)[/tex] into [tex]\( d(x) \)[/tex]:
[tex]\[ d(4) = \sqrt{4 + 5} = \sqrt{9} = 3 \][/tex]

So:
[tex]\[ (d \circ a)(2) = 3 \][/tex]

### c. [tex]\((c \circ m)(x) = c(m(x))\)[/tex]

First, substitute [tex]\( m(x) \)[/tex] into [tex]\( c(x) \)[/tex]:
[tex]\[ m(x) = 5x - 3 \][/tex]

Next, substitute [tex]\( m(x) \)[/tex] into [tex]\( c(x) \)[/tex]:
[tex]\[ c(m(x)) = c(5x - 3) \][/tex]

Substitute [tex]\( 5x - 3 \)[/tex] into [tex]\( c(x) \)[/tex]:
[tex]\[ c(5x - 3) = 5(5x - 3)^2 + 17(5x - 3) - 12 \][/tex]

Now, simplify:
[tex]\[ (5x - 3)^2 = 25x^2 - 30x + 9 \][/tex]
[tex]\[ c(5x - 3) = 5(25x^2 - 30x + 9) + 17(5x - 3) - 12 \][/tex]

Distribute the constants:
[tex]\[ 5(25x^2 - 30x + 9) + 17(5x - 3) - 12 \][/tex]
[tex]\[ = 125x^2 - 150x + 45 + 85x - 51 - 12 \][/tex]

Combine like terms:
[tex]\[ = 125x^2 - 65x - 18 \][/tex]

So:
[tex]\[ (c \circ m)(x) = 125x^2 - 65x - 18 \][/tex]

### d. [tex]\((m \circ c)(x) = m(c(x))\)[/tex]

First, substitute [tex]\( c(x) \)[/tex] into [tex]\( m(x) \)[/tex]:
[tex]\[ c(x) = 5x^2 + 17x - 12 \][/tex]

Next, substitute [tex]\( c(x) \)[/tex] into [tex]\( m(x) \)[/tex]:
[tex]\[ m(c(x)) = m(5x^2 + 17x - 12) \][/tex]

Substitute [tex]\( 5x^2 + 17x - 12 \)[/tex] into [tex]\( m(x) \)[/tex]:
[tex]\[ m(5x^2 + 17x - 12) = 5(5x^2 + 17x - 12) - 3 \][/tex]

Distribute the 5:
[tex]\[ = 25x^2 + 85x - 60 - 3 \][/tex]

Combine like terms:
[tex]\[ = 25x^2 + 85x - 63 \][/tex]

So:
[tex]\[ (m \circ c)(x) = 25x^2 + 85x - 63 \][/tex]

### Summary of results

a. [tex]\((d \circ a)(x) = \sqrt{x + 7}\)[/tex]

b. [tex]\((d \circ a)(2) = 3\)[/tex]

c. [tex]\((c \circ m)(x) = 125x^2 - 65x - 18\)[/tex]

d. [tex]\((m \circ c)(x) = 25x^2 + 85x - 63\)[/tex]