Given fxx29 gx2x hxx3 Find the following 1 f3 2 g3 3 h6 4 fg
Given f(x)=x2-9, g(x)=2x, h(x)=x-3 Find the following 1.) f(3) 2.) g(3) 3.) h(6) 4.) (f+g)x 5.) (f+g) (3) 6.) (f-h)(-3) 7.) (g+h)(1/4) 8.) (h-g)(x) 9.) (f.g) x 10. (f.g) (1) 11.) (g.h) 12.) (h.g)
Solution
given,
f(x)=x2-9,g(x)=2x,h(x)=x-3.
We need to find out following values.
1.) f(3)
To find f(3) we have to substitute x with 3 in funtion f(x)
i.e., (3)^2-9=9-9=0
Therefore, f(3)=0
2.)g(3)
To find g(3) we have to substitute x with 3 in funtion g(x)
i.e.,2(3)=6
Therefore, g(3)=6
3.)h(6)
To find h(6) we have to substitute x with 6 in funtion h(x)
i.e.,6-3=3
Therefore, h(6)=3
4.)(f+g)x
To find (f+g)x we have to add functions f(x) and g(x)
i.e.,x2-9+2x
Therefore, (f+g)x=x2+2x-9
5.)(f+g)3
From 4th problem (f+g)x=x2+2x-9
substitute x with 3 den we get (f+g)3
i.e.,3^2+2(3)-9=6
Therefore, (f+g)3=6
6.)(f-h)(-3)
Similarly subtract function f(x) and h(x) then substitute x with -3
i.e.,x2-9-(x-3)=x2-9-x+3=x2-x-6
(f-h)(-3)=(-3)^2-(-3)-6=6
Therefore, (f-h)(-3)=6
7.)(g+h)(1/4)
Similarly add functions g(x) and h(x) then substitute x with 1/4
i.e.,2x+x-3=3x-3
(g+h)(1/4)=3(1/4)-3=(-9/4)
Therefore, (g+h)(1/4)=(-9/4)
8.)(h-g)(x)
Subtract function h(x) and g(x)
i.e.,x-3-(2x)=x-3-2x=-x-3
Therefore (h-g)(x)=-x-3
9.)(f.g)x
Multiply function f(x) and g(x)
i.e.,(x2-9)(2x)=2x3-18x
Therefore, (f.g)x=2x3-18x
10.)(f.g)(1)
From problem.9 we got (f.g)x=2x3-18x
By substituting x with 1 we get,
(f.g)(1)=2(1)-18(1)=2-18=-16
Therefore, (f.g)(1)=-16
11.)(g.h)x
Multiply functions g(x) and h(x) we get,
(2x)(x-3)=2x2-6x
Therefore, (g.h)x=2x2-6x
12.)(h.g)x
Multiply functions h(x) and g(x) we get,
(x-3)(2x)=2x2-6x
Therefore,(h.g)x=2x2-6x


