<span>а) (3у</span>²<span>-3у+1)-(4у-2)= 3y</span>²-3y+1-4y+2=3y²-7y+3
<span>б) 4b</span>³(3b²+b)=4b^4(3b+1)<span>
</span>
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Lg^2x+4(lg10+lgx)=1
Lg^2x+4+4lgx=1
lg^2x+4lgx+3=0
Пусть lgx = t,
t^2 + 4t + 3 = 0
t1,2= (-4+-(16-12))/2= (-4+-2)/2
t1=-3
t2=-1
Обратная замена,
lgx = -3; x=1/1000
lgx = -1; x=1/10