मराठी

If F : R → R, F(X) = X3 and G: R → R , G(X) = 2x2 + 1, and R is the Set of Real Numbers, Then Find Fog(X) and Gof (X) - Mathematics

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प्रश्न

If f : R → R, f(x) = x and g: R → R , g(x) =  2x+ 1, and R is the set of real numbers, then find fog(x) and gof (x)

बेरीज
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उत्तर

f : R → R and g : R → R 
∴ f (g(x)) and g(f(x)) both are defined over common domain
f(g(x))= (g(x))= (2x2 + 1)3 
= 8x+ 12x+ 6x+ 1
g(f (x)) = 2(f(x))+ 1 = 2(x3)+ 1 = 2x+ 1

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