Question

 

 

Sin^2 (39градусов)+сos39×sin51-2, 7

 

 

Answer 1

sin^2(39)+cos39*sin51-2,7=sin^2(39)+cos39*sin(90-39)-2,7=sin^2(39)+cos^2(39)-2,7=1-2,7=-1,7

Answer 2

Sin^2 (39градусов)+сos39×sin51-2, 7=sin²39+cos39sin(90-31) - 2.7= sin²39+cos²39-2.7=1-2.7=-1.7