a1=1
a5=81
1) a5=a1+4d
81=1+4d
4d=80
d=20
2) a2=a1+1d=1+20=21
3) a3=a1+2d=1+40=41
4) a4=a1+3d=1+60=61
Ответ:21;41;61.
6x-4y=13
4y=6x-13
y=1/4(6x-13)
A(1/6,y)
y=(1/4)(6.1/6-13)=(1/4)(1-13)=(1/4)(-12)=-3
y=-3
A(1/6,-3)
1) а2 + 4а2 - 4ас + с2 = 5а2 - 4ас + с2
2) 25t2 + 70tz + 49z2 - 70tz = 25t2 + 49z2
3) 16b2 - (a2 - 8ab + 16b2) = 16b2 - a2 + 8ab - 16 b2 = -a2 + 8ab
(b+4)¹¹×(b+4)^5×(b+4)^5×(b+4)^6=<span>(b+4)^27</span>