log_3 67,5 - log_3 2,5 = log_3 67,5/2,5 = log_3 27 = 3
X^2 + x - 56 = 0
D = b^2 - 4ac = 1+ 224 = 225
√D = 15
x1 = (-1 + 15) /2 = 7
х2 = (-1 - 15) /2 = -16/2 = -8
(7х-99):10=-5
0,7х-9,9=-5
0,7х=-5+9,9
0,7х=4,9
х=7
2с-4/сd-2d=2(c-2)/d(c-2)=2/d=2/5=0.4
<span>2sin^2x+2sin^2x*cos^2x/sin^2x+1</span>
<span><span>2sin^2x+2cos^2x+1</span></span>
<span><span>ответ 2sin^2x+2cos^2x+1</span></span>
<span><span>можно еще дальше решить:</span></span>
<span><span>2sin^2+2cos^2x=1*2=2</span></span>
<span><span>2+1=3</span></span>