Question

If c(x) = 4x-2 and d(x) = x2+5x what is (cod)(x)

Answer 1

Solution :

Given c(x) = 4x-2 ---( 1 )

d(x) = x² + 5x -----( 2 )

(cod)(x)

= c[d(x)]

= c[x² + 5x ] [ from ( 2 ) ]

= 4( x² + 5x )² - 2

= 4[ (x²)² + 2 × x² × (5x) + ( 5x )²]- 2

= 4( x⁴ + 10x³+ 25x² ) - 2

= 4x⁴ + 40x³ + 100x² - 2

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