1. **Problem statement:** We are given two functions:
$$f_9(w) = w^2 + 2$$
$$g_9(v) = 3v^2 + 6v - 6$$
We need to find the composition $$f_9(g_9(x))$$, which means substituting $$g_9(x)$$ into $$f_9$$.
2. **Formula and rules:** The composition of functions is defined as:
$$f(g(x)) = f\bigl(g(x)\bigr)$$
This means wherever there is a $$w$$ in $$f_9(w)$$, replace it with $$g_9(x)$$.
3. **Substitute:**
$$f_9(g_9(x)) = \bigl(g_9(x)\bigr)^2 + 2$$
Substitute $$g_9(x) = 3x^2 + 6x - 6$$:
$$= \left(3x^2 + 6x - 6\right)^2 + 2$$
4. **Expand the square:**
Use the formula $$(a+b+c)^2 = a^2 + b^2 + c^2 + 2ab + 2ac + 2bc$$ with $$a=3x^2$$, $$b=6x$$, $$c=-6$$:
$$= (3x^2)^2 + (6x)^2 + (-6)^2 + 2(3x^2)(6x) + 2(3x^2)(-6) + 2(6x)(-6) + 2$$
Calculate each term:
$$= 9x^4 + 36x^2 + 36 + 36x^3 - 36x^2 - 72x + 2$$
5. **Combine like terms:**
$$9x^4 + 36x^3 + (36x^2 - 36x^2) - 72x + (36 + 2)$$
Simplify:
$$9x^4 + 36x^3 - 72x + 38$$
6. **Final expression:**
$$f_9(g_9(x)) = 9x^4 + 36x^3 - 72x + 38$$
7. **Evaluate at points:**
- At $$x = -1$$:
$$9(-1)^4 + 36(-1)^3 - 72(-1) + 38 = 9(1) - 36 + 72 + 38 = 83$$
- At $$x = 0$$:
$$9(0)^4 + 36(0)^3 - 72(0) + 38 = 38$$
- At $$x = 2$$:
$$9(2)^4 + 36(2)^3 - 72(2) + 38 = 9(16) + 36(8) - 144 + 38 = 144 + 288 - 144 + 38 = 326$$
8. **Interpretation:**
You can plot these points on a coordinate system with axes $$y$$ and $$z$$, where $$x$$ values are on the number line and the corresponding $$f_9(g_9(x))$$ values are the points in the $$y-z$$ plane.
Function Composition 36Eb22
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.