1 - √5; 1 + √5.
Объяснение:
10t = 5(t² - 4)
10t = 5t² - 20
5t² - 10t - 20 = 0
D = 100 + 400 = 500
√D = √500 = 10√5
x1 = (10 - 10√5) / 10 = 1 - √5
x2 = (10 + 10√5) / 10 = 1 + √5
ответ: 1 - √5; 1 + √5.
(-1;3)
10t=5t²-20
-5t²+10t+20=0 |:5
-x²+2t+4=0
D= b²-4ac= 4-4×(-1)×4=16
x1=-b+√D/2×a= -2+ 4/-2= -1
x2=-b-√D/2×a= -2-4/-2 = 3
1 - √5; 1 + √5.
Объяснение:
10t = 5(t² - 4)
10t = 5t² - 20
5t² - 10t - 20 = 0
D = 100 + 400 = 500
√D = √500 = 10√5
x1 = (10 - 10√5) / 10 = 1 - √5
x2 = (10 + 10√5) / 10 = 1 + √5
ответ: 1 - √5; 1 + √5.
(-1;3)
Объяснение:
10t=5t²-20
-5t²+10t+20=0 |:5
-x²+2t+4=0
D= b²-4ac= 4-4×(-1)×4=16
x1=-b+√D/2×a= -2+ 4/-2= -1
x2=-b-√D/2×a= -2-4/-2 = 3