A)5√7/2=√(7*25/4)=√(175/4)=√43,75
√17
1/2√62=√(1/(4*62)=√(1/248)
1/2√62;√14;5√7/2
b)8√0,2=√(64*0,2)=√12,8
√41
2/5√160=√(4/25*1/160)=√(1/1000)
2/5√160;8√0,2;√41
= 16X^2 + 0.8XY + 0.01Y^2
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1)4^(n+1) /2^(2n-1) = 2^(2n+2) / 2^(2n-1) = 2^(2n+2-2n+1) = 2³ = 8
2) 5^(2n+3) / 25^(n-1) = 5^(2n+3) / 5^(2n-2) = 5^(2n+3-2n+2) = 5^5 = 3125
3) [(-5)^(6n+2) * 5^(-4n)] : 25^n = 5^(6n+2-4n) / 5^2n = 5^(2n+2) / 5^2n =
= 5^(2n+2-2n) = 5² = 25
4) 18^(n+3) / [3^(2n+5) * 2^(n-2)] = [2^(n+3) * 3^(2n+6)] / [3^(2n+5) * 2^(n-2)]=
= 2^(n+3-n+2) * 3^(2n+6-2n-5) = 2^5 * 3 = 32 * 3 = 96
<span>х(х+3)=4
х²+3х-4=0
D=9-4·(-4)=25
x=(-3-5)\2=-4 или х=(-3+5)/2=1
Ответ. -4; 1
</span>
2.8x-3(2x-1)=2.8-3.19x
2.8x-6x+3=2.8-3.19x
2.8x-6x+3-2.8+3.19x=0
-0.01x+0.2=0
-0.01x=-0.2
x=(-0.2):(-0.01)=20
x=20