1,27:1000=0,00127
5,41:10000=0,000541
Следовательно 1,27*10^-3 больше
10ab+(-5a+b)² = 10ab +(b-5a)² = 10ab+ b² -10ab +25a² = b²+25a²
при a=√10 и b=√5 b²+25a²=(√5)²+25(√10)² = 5+25*10 =5+250=255
<span>cos a=√1-(-√3/2)²=√1-3/2=√1/4=1/2</span>
<span>а)(2а-1)</span>²=(2a)²-2*2a*1+1²=4a²-4a+1<span>
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б)(х+3у)^2==x</span>²+2x*3y+(3y)²=x²+6xy+9y²
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в)(1/5х-у)(1/5х+у)=(1/5x)</span>²-y²=1/25x²-y²
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