Jawaban:

1. (f+g)(x) = 5x – 2

2. (f-g)(x) = – x + 8

3. (3f)(x) = 6x + 9

4. (fg)(x) = 15x² – 10x – 15

Penjelasan dengan langkah-langkah:

diketahui

f(x) = 2x + 3, dan

g(x) = 3x – 5.

ditanya

Nilai dari (f+g)(x), (f-g)(x), (3f)(x), dan (fg)(x) adalah ... ?

dijawab

• (f+g)(x) = ... ?

= f(x) + g(x)

= (2x + 3) + (3x – 5)

= 2x + 3x + 3 – 5

= 5x – 2

• (f-g)(x) = ... ?

= f(x) - g(x)

= (2x + 3) - (3x – 5)

= 2x – 3x + 3 + 5

= – x + 8

• (3f)(x) = ... ?

= 3.f(x)

= 3.(2x + 3)

= 6x + 9

• (fg)(x) = ... ?

= f(x) × g(x)

= (2x + 3) × (3x – 5)

= 2x.(3x – 5) + 3.(3x – 5)

= 6x² – 10x + 9x² – 15

= 6x² + 9x² – 10x – 15

= 15x² – 10x – 15

Semoga Membantu Ya !