1)cos 30° tg 60°ctg45°=(√3/2)*√3*1=3/2=1.5
2)7cos ²α+7sin²α=7*(cos ²α+sin²α)=7*1=7
3)tg49°- ctg49°=(sin49°/cos49°)-(cos49°/sin49°)=
2(sin²49°-cos²49°)/(2sin49°cos49°)=-2cos98°/sin98°=-2ctg98°=-2tg8°
4)sin ²α + cos²α+ 5=1+5=6
5) 2sin 15° cos 15°=sin30°=0.5
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1)cos 30° tg 60°ctg45°=(√3/2)*√3*1=3/2=1.5
2)7cos ²α+7sin²α=7*(cos ²α+sin²α)=7*1=7
3)tg49°- ctg49°=(sin49°/cos49°)-(cos49°/sin49°)=
2(sin²49°-cos²49°)/(2sin49°cos49°)=-2cos98°/sin98°=-2ctg98°=-2tg8°
4)sin ²α + cos²α+ 5=1+5=6
5) 2sin 15° cos 15°=sin30°=0.5