jika log(xpangkat2 +7x+20)=1 ,maka (x1 +x2)kuadrat=4x1.x2

jawab

log (x² + 7x +20) = 1
x² + 7x + 20 = 10
x² + 7x + 10 = 0
x1 + x2= -7
x1 . x2 = 10

(x1 + x2)²   - 4 x1 x2 =
= 7² - 4(10)
= 49  -40
= 9