Persamaan kuadrat 5x2 – x – 2 = 0 mempunyai akar-akar α dan β . Nilai dari α 2 + β 2 = ....

jwab


5x² - x - 2 = 0
a= 5
b = -1
c = -2

α + β =  -b/a = 1/5
α.β = c/a = -2/5

α² + β² = (α + β)² - 2αβ = (1/5)² - 2(-2/5)
= 1/25 + 4/5
= 21/25