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Find [g ° h](x) and [h ° g](x) , if they exist. g(x)=x+6 and h(x)=3x2 YALL PLEASE I NEED HELP :((

User Sachin J
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1 Answer

7 votes

Answer:

a) [g ° h](x) = 3x² +6

b) [h ° g](x) =3 x²+36x+108

Explanation:

Explanation:-

a)

Given g(x) = x+6 and h(x) = 3x²

Given [g ° h](x) = g(h(x))

= g(3x²) (∵ h(x) =3x²)

= (3x²)+6 (∵ g(x) =x+6)

∴ [g ° h](x) = 3x² +6

b)

Given [h ° g](x) = h (g(x))

= h(x+6) (∵ g(x) =x+6)

= 3 (x+6)² (∵ h(x) =3x²)

= 3 (x²+2(6)x+36) (∵ (a + b)² = a²+2ab+b²)

= 3 (x²+12x+36)

= 3 x²+36x+108)

∴ [h ° g](x) =3 x²+36x+108

User Dnsko
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