Math Problem Statement
Tentukan nilai dari (f o g)(0), (g o f)(3), dan solusi dari (g o f)(x) = 8, maka x?
Solution
From the image you provided, the question appears to involve composite functions, where f(x) and g(x) are given as:
- f(x)=2x+1
- g(x)=x2−3x+4
The task is to find various composite functions and values, such as:
- (f∘g)(0)
- (g∘f)(3)
- (g∘f)(x)=8, solve for x
Step-by-Step Solution:
1. (f∘g)(0)
This is the value of f(g(0)).
- First, find g(0):
g(0)=02−3(0)+4=4
- Now, substitute g(0)=4 into f(x):
f(4)=2(4)+1=8+1=9
Thus, (f∘g)(0)=9.
2. (g∘f)(3)
This is the value of g(f(3)).
- First, find f(3):
f(3)=2(3)+1=6+1=7
- Now, substitute f(3)=7 into g(x):
g(7)=72−3(7)+4=49−21+4=32
Thus, (g∘f)(3)=32.
3. Solve (g∘f)(x)=8
This means we need to solve for x such that g(f(x))=8.
- First, find f(x):
f(x)=2x+1
- Now, substitute f(x) into g(x):
g(f(x))=(2x+1)2−3(2x+1)+4
- Simplify the expression:
(2x+1)2=4x2+4x+1
−3(2x+1)=−6x−3
g(f(x))=4x2+4x+1−6x−3+4=4x2−2x+2
- Now, solve 4x2−2x+2=8:
4x2−2x+2−8=0
4x2−2x−6=0
Divide through by 2:
2x2−x−3=0
- Solve using the quadratic formula:
x=2(2)−(−1)±(−1)2−4(2)(−3)
x=41±1+24=41±25
x=41±5
Thus, x=41+5=46=1.5 or x=41−5=4−4=−1.
So, the solutions are x=1.5 and x=−1.
Would you like more details or have any questions?
Here are 5 related questions for further practice:
- What is (f∘g)(x) in general form?
- How would you solve (f∘g)(x)=5?
- Can you find (g∘f)(0)?
- What are the solutions to g(f(x))=16?
- If f(x)=3x−2 and g(x)=x2+x+1, what is (f∘g)(2)?
Tip: Always check the order of composition carefully—f(g(x)) is not the same as g(f(x))!