jabarkanlah kemudian sederhanakanlah. a.(6 – 3x)(3x + 1) b.(x – y + 2)(x – y + 3) c.(x²– 4)²

a][
(6 - 3x)(3x + 1)
= 6(3x + 1) - 3x(3x + 1)
= 18x + 6 - 9x² - 3x
= -9x² + 15x + 6

b][
(x - y + 2)(x - y + 3)
= x(x - y + 3) - y(x - y + 3) + 2(x - y + 3)
= x² - xy + 3x - xy + y² - 3y + 2x - 2y + 6
= x² + 5x + y² - 5y - 2xy + 6
= (x - y)² + 5(x - y) + 6

c][
(x² - 4)²
= (x²)² - 2(x²)(4) + 4²
= x⁴ - 8x² + 16

➡ (a - b)² = a² - 2ab + b²