А)5х^4 +2; б) 72х^5; В)cosх+3 sinх; г) -4*sin(4х-п/3)
9х^2-30х+25-4х^2+4х-1-24=0
5х^2-26х=0
х(5х-26)=0
x1=0
x2=26/5=5 целых1/5
Проверка:
(3•0-5)^2-(2•0-1)^2=24
25-1=24
24=24
(3•26/5-5)^2-(2•26/5-1)^2=24
(78/5-5)^2-(52/5-1)^2=24
53/5^2-47/5^2=24
2809/25-2209/25=24
600/25=24
24=24
Ответ: х1=0; х2=5целых1/5
5/12 - 7/9у = 10 5/12 - 3у
- 7/9у + 3у = 10 5/12 - 5/12
2 2/9у = 10
20/9у = 10
у = 10 : 20/9
у = 10 * 9/20
у = 9/2 = 4 целых 1/2 = 4,5
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Проверка: 5/12 - 7/9 * 9/2 = 10 5/12 - 3 * 9/2
5/12 - 7/2 = 10 5/12 - 27/2
5/12 - 42/12 = 125/12 - 162/12
- 37/12 = - 37/12