cos^a/sin^2a=cos^2a/(1-cos^2a)
9*(1-cos^2a)=cos^2a
9=10cos^2a
cos^2a=0,9
(2*0,9+3)/(5+3*0,9)=4,8/7,7=48/77
Ответ: С) 48/77
Y=x+(lnx)/x, x bolše čem 0
(lnx)´=1/x
x´= 1
(u/v)´= (u´v-uv´)/v²
y´=1 + (1/x . x -lnx .1)/x²=1+(1-lnx)/x²=(-lnx)/x²
4=√16
3√2=√18
2√6=√24
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√15, √16, √17, √18, √24
√15, 4, √17, 3√2, 2√6
....... .....иоо ..........