4^(15)/8^(9) = 2^(30) /2^(27)=2^(30-27) =2^(3) =8
<span> наверно имеется в виду: y=x^2-4x+5</span>
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5x-2y=c
P(2,4), x=2,y=4
5.2-2.4=c, c=10-8, c=2
5x-2y=2
-2y=-5x+2
2y=5x-2
y=2,5x-1
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Grafikom prjamaja proxodit točkami (2,4) i (0,-1).
A25=a1+24d=-2+24*5=118 , an=a1-(n-1)*d