1) a1=–8; a2=–6,5; a3=–5
d=a2–a1=–6,5+8=1,5
a10=a1+9d=–8+13,5=5,5
S10=(2a1+9d)/2 *10=(-16+13,5)/2 *10=
=–12,5
2) b1=16/27; b2=16/9; b3=16/3
q=b2:b1=16/9:16/27=(16*27)/(9*16)=3
b8=b1*q^7=16/27*2187=1296
3) a3+a6=3; a2>a7 на 15
a2–a7=15
a3=a1+2d; a6=a1+5d;
a2=a1+d; a7=a1+6d
a1+2d+a1+5d=3; 2a1+7d=3
a1+d–a1–6d=15;
–5d=15
d=–3
2a1+7*(-3)=3
2a1–21=3
2a1=24
a1=12
a2=a1+d=12–3=9
(Х-9)²-9Х² = Х²-18Х+81-9Х² = -8Х²-18Х+81
Y=-2x
y(-2)=-2*(-2)=4
y(-1)=-2*(-1)=2
y(0)=-2*0=0
y(2)=-2*2=-4
y=20x+4
y(-2)=20*(-2)+4=-40+4=-36
y(-1)=20*(-1)+4=-20+4=-16
y(0)=20*0+4=4
y(2)=20*2+4=40+4=44
s=60t
s(3.5)=60*3.5=210
s(5)=60*5=300
<span>y=2x-1
y(10)=2*10+1=21
y(-4.5)=-4.5*2+1=-8
y(15)=15*2-1=29
y(251)=251*2-1=501
</span><span><span>2x-1=</span>-19
2x=-18
x=-9
</span><span>2x-1=-57
2x=-56
x=-28
</span><span><span>2x-1=</span>205</span>
2x=206
x=103
p(x)=(2x+1)/3
<span>p(-12)=(-12*2+1)/3=-23/3
p(2.1)</span>=(2.1*2+1)/3=52/30=26/15
(2x+1)/3=2.4
2x+1=7.2
2x=6.2
x=3.1
(2x+1)/3=-9
2x+1=-27
2x=-26
x=-13