Questions: Evaluate the function f(r)=sqrt(r+3)+9 at the given values of the independent variable and simplify.
a. f(-3)
b. f(61)
c. f(x-3)
Transcript text: Evaluate the function $f(r)=\sqrt{r+3}+9$ at the given values of the independent variable and simplify.
a. $f(-3)$
b. $f(61)$
c. $f(x-3)$
Solution
Solution Steps
To evaluate the function \( f(r) = \sqrt{r+3} + 9 \) at the given values of the independent variable, we will substitute the values into the function and simplify the result.
a. For \( f(-3) \), substitute \( r = -3 \) into the function.
b. For \( f(61) \), substitute \( r = 61 \) into the function.
c. For \( f(x-3) \), substitute \( r = x-3 \) into the function.
Step 1: Evaluate \( f(-3) \)
To evaluate \( f(-3) \), substitute \( r = -3 \) into the function \( f(r) = \sqrt{r+3} + 9 \):
\[
f(-3) = \sqrt{-3 + 3} + 9 = \sqrt{0} + 9 = 0 + 9 = 9
\]
Step 2: Evaluate \( f(61) \)
To evaluate \( f(61) \), substitute \( r = 61 \) into the function \( f(r) = \sqrt{r+3} + 9 \):
\[
f(61) = \sqrt{61 + 3} + 9 = \sqrt{64} + 9 = 8 + 9 = 17
\]
Step 3: Evaluate \( f(x-3) \)
To evaluate \( f(x-3) \), substitute \( r = x-3 \) into the function \( f(r) = \sqrt{r+3} + 9 \):
\[
f(x-3) = \sqrt{(x-3) + 3} + 9 = \sqrt{x} + 9
\]
For \( x = 5 \):
\[
f(5-3) = \sqrt{5} + 9 \approx 2.2361 + 9 = 11.2361
\]