If f(x)=6x^3+5x,g(x)=3x^2+5,and h(x)=9x^2-8 what is the degree of f(g(h(x))) awer choices are a.2 b.3 3.7 4.12

To find f(g(h(x))), we need to find g(h(x)) first. To do that we are going to evaluate the function g(x) at h(x):
We know that [tex]h(x)=9x^2-8[/tex] and [tex]g(x)=3x^2+5[/tex]
[tex]g(h(x))=g(9x^2-8)=3(9x^2-8)^2+5[/tex]
[tex]=3(81x^4-144x^2+64)+5[/tex]
[tex]=243x^4-432x^2+192+5[/tex]
[tex]=243x^4-432x^2+197[/tex]

Now that we know that [tex]g(h(x))=243x^4-432x^2+197[/tex], to find [tex]f(g(h(x)))[/tex] we are going to evaluate [tex]f[/tex] at [tex]243x^4-432x^2+197[/tex]
[tex]f(g(h(x)))=f(243x^4-432x^2+197)[/tex]
[tex]f(243x^4-432x^2+197)=6(243x^4-432x^2+197)^3[/tex][tex]+5(243x^4-432x^2+197)[/tex]

[tex]=86093442x^{12}-459165024x^{10}+1025681130x^8-1228219200x^6[/tex][tex]+83152048x^4-301780944x^2+45873223[/tex]

Since the degree of a polynomial is the highest degree of its monomials, we can conclude that the degree of f(g(h(x))) is 12