1
sin45°cos60°+3tan30°
=√2/2 * 1/2 + 3 * (√3/3)
= √2/4 + √3
2
（1+sin45°+sin30°）（1-cos45°+cos60°）
=(1+sin30° + sin45°)* (1-cos45° + sin30°)
=[(1+sin30°) + sin45°] * [(1+sin30°) - sin45°]
=(1+sin30°)^2 - sin45°^2
=(1+ 1/2)^2 - (√2/2)^2
= 9/4 - 2/4
= 7/4
3Rt△ABC中cosA = b/c,
所以b= c* cosA = 10 * cos60° = 10 * (1/2) = 5
sinB = b/c = 5/10 = 1/2=0.5