Question

Akar akar persamaan 3x^2 + 5x + m = 0 adalah a dan b. jika a^2 + b^2 = 5, maka nilai m adalah...

Answer 1

3x² + 5x + m = 0
a+b = -b/a = -5/3
a.b = c/a = m/3

a² + b² = 5
(a+b)² - 2ab = 5
(-5/3)² - 2 (m/3) = 5
25/9 - 2m/3 = 5 --> kedua ruas dikali 9
25 - 6m = 45
-6m = 45 - 25
-6m = 20
m = -20/6
m = -10/3

semoga membantu :)

Answer 2

3x² + 5x + m = 0
a+b = -b/a = -5/3
a.b = c/a = m/3

a² + b² = 5
(a+b)² - 2ab = 5
(-5/3)² - 2 (m/3) = 5
25/9 - 2m/3 = 5
25 - 6m = 45
-6m = 45 - 25
-6m = 20
m = -20/6
m = -10/3