Diketahui f(x) = 2x - 1 dan g(x) = 3x² + 4 . Tentukan: a. (f ° g) (x) b. ( g° f) (x) c.( f° g) (10) d. ( g° f) ( -1)
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(fog)(x)
= f [ g(x) ]
= 2 (3x² + 4) - 1
= 6x² + 8 - 1
= 6x² + 7
(gof)(x)
= g [ f(x) ]
= 3 (2x - 1)² + 4
= 3 (4x² - 4x + 1) + 4
= 12x² - 12x + 3 + 4
= 12x² - 12x + 7
(fog) (10)
= 6 (10)² + 7
= 6 ( 100 ) + 7
= 600 + 7
= 607
(gof) ( - 1 )
= 12x² - 12x + 7
= 12 ( - 1 )² - 12 ( - 1 ) + 7
= 12 ( 1 ) + 12 + 7
= 12 + 12 + 7
= 24 + 7
= 31
