-2, т.к. y=13-5*3=13-15=-2
Ответ: y=-2
А)х^14
b)x^15
c)x^18
d)81x^8
X+y=-2
y²-3x=6
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3x+3y=-6
-3x+y²=6
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y²+3y=0 , y(y+3)=0
a)y=0, x=-2
b)y=-3, x=1
A∈Iч. b∈IIIч.
<span>cos(a+b)=cosacosb-sinasinb
</span>sina=
0.6cosb=0.8sinb
cosb= -0.8
A2+a5 = 8
a3+a7 = 14
a1+d+a1+4d = 8
a1+2d +a1+6d = 14
2a1+5d = 8
2a1+8d = 14
3d = 6
d = 2
2a1+5*2 = 8
2a1 = -2
a1 = -1