2sin2x<1
sin2x<1/2
-<span>π</span>/6<2x<<span>π/6</span>
<span>-<span>π/12<x<<span>π/12</span></span></span>
<span><span><span>x<span>∈(-<span>π/12;<span>π/12)</span></span></span></span></span></span>
У^2 4×^2
--- - ----
у-2х у-2×
у^2-4×^2
--------
у-2×
Угол КМР+ угол МАР+ угол АРМ=180" по т.4.4
75"+60"+ угол АРМ=180"
угол АРМ=180"-75"-60"=45"