48n/16n-1*3n-3 = 144n^2/16n-1 - 3 = 144n^2-3(16n-1)/16n-1 = 144n^2-48n+3/16n-1
= - 36 : 9 - 9 = - 4 - 9 = - 13
sin^2a=0.25
cos^2a=1-sin^2a=1-0.25=0.75
4cos2a=4(cos^2a-sin^2a)=4(0.75-0.25)=<em><u>2</u></em>
<em><u>Ответ: 2</u></em>
Ответ: ху+3х-5ху-2х=-4ху+х