361 ^ - 1/2 = = 1 / 19
216 ^ 1/3 = ( 6 ^3 ) ^ 1/3 = 6
343 ^ 2/3 = ( 7 ^3 ) ^ 2/3 = 7 ^ 2 = 49
125 ^ 1 ( 1/3 ) = 125 ^ 4/3 = ( 5^3 )^4/3 = 5 ^ 4 = 625
--------------------------------------------
6 + 49 - 625 = 55 - 625 = - 570
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1 / 19 * ( - 570 ) = - 570/19 = - 30
1)2(a1+a2+a3+a4)=a5+a6+a7
2(4a1+6d)=3a1+15d
8a1+12d=3a1+15d
5a1=3d
a8=38
a1+7d=38
(3:5)d+7d=38
d=5
a1=3
a2=a1+d=3+5=8
2)5226
1)Пусть x^2=y,(y>=0) тогда
y^2-5y-36=0
D=25+144=169=13^2
y1=(5+13)/2=9
y2=(5-13)/2= - 4-не удовлетворяет условию
2) если y=9, то x=3или x=-3
(x-2)² - 5² < 0
(x-2-5)(x-2+5) < 0
(x-7)(x+3) < 0
x=7 x= -3
+ - +
------- -3 ---------- 7 -----------
\\\\\\\\\\\\
x∈ (-3; 7)