. 25-10*y+y^2-(5+y)^2
. 25-10*y+y^2-(25+10*y+y^2)
. 25-10*y+y^2-25-10*y-y^2
. -10*y+y^2-10*y-y^2
. -20*y+y^2-y^2
. -20*y
х3*х7:х=х9.....................
7/10-11/30=1/3 1/3*<span>(-1 2/7)=-3/7 -1/3*(1 2/7)=-3/7
1/4-11/24=-5/24 -5/24 :2 11/12=-1/14
-3/7-1/14=-1/2</span>
<span>2log6 2+log6 9=log6 2^2+log6 9=log6 4*9=log6 36= log6 6^2=2
loga bc= loga b +loga c</span>