Let’s start solving some of the questions from the image.
5. The given functions are f(x)=3x2+2x−1 and g(x)=x−1. If we form h(x)=g(x)f(x), then what is h(2)?
To solve this:
- We calculate f(2) and g(2) first.
For f(2):
f(2)=3(2)2+2(2)−1=3(4)+4−1=12+4−1=15
For g(2):
g(2)=2−1=1
So, h(2)=g(2)f(2)=115=15.
Answer: b. 15
6. The function is f(x)=2x2−5x+3. Find f(3).
We substitute x=3 into the function:
f(3)=2(3)2−5(3)+3=2(9)−15+3=18−15+3=6
Answer: c. 6
7. The given functions are f(x)=3x−1 and g(x)=2x2+3. Find the value of the composite function (g∘f)(x).
First, find f(x):
f(x)=3x−1
Now substitute f(x) into g(x):
g(f(x))=g(3x−1)=2(3x−1)2+3
Expand (3x−1)2:
(3x−1)2=9x2−6x+1
Now substitute this back into g(f(x)):
g(f(x))=2(9x2−6x+1)+3=18x2−12x+2+3=18x2−12x+5
Answer: b. 18x^2 - 12x + 5
8. The functions are f(x)=2x2+3 and g(x)=x+4. Find (g∘f)(2).
First, find f(2):
f(2)=2(2)2+3=2(4)+3=8+3=11
Now, find g(f(2))=g(11):
g(11)=11+4=15
Answer: e. 15
9. The functions are f(x−1)=5x2+6x−6 and g(x)=ax+1. If (g∘f)(1)=−51, find f(a+1).
We are asked to find f(a+1). First, substitute x=1 into f(x−1):
f(1−1)=5(1)2+6(1)−6=5+6−6=5
Then, since g(1)=−51, we must solve for f(a+1).
This part is complex, let me confirm details to continue.
Let me know if you'd like further details on these, or if I can assist with any other specific questions!