数学三角函数2求SIN^10+C
楼上的：按计算器也可以的
解：原式=SIN^10+COS^40+SIN10*COS(10+30)
=sin^10+cos40*(sin10+cos(10+30))
=sin^10+cos40*(sin10+cos10cos30-1/2sin30)
=sin^10+cos40*cos20
=sin^10+sin50*cos20
=sin^10+(sin30cos20+cos30sin20)*cos20
=sin^10+1/2(2sin30cos^20+1/2-1/2+2cos30sin20cos20)
=sin^10+1/4+1/2sin70
=sin^10+1/2cos20+1/4
=si...全部
楼上的：按计算器也可以的
解：原式=SIN^10+COS^40+SIN10*COS(10+30)
=sin^10+cos40*(sin10+cos(10+30))
=sin^10+cos40*(sin10+cos10cos30-1/2sin30)
=sin^10+cos40*cos20
=sin^10+sin50*cos20
=sin^10+(sin30cos20+cos30sin20)*cos20
=sin^10+1/2(2sin30cos^20+1/2-1/2+2cos30sin20cos20)
=sin^10+1/4+1/2sin70
=sin^10+1/2cos20+1/4
=sin^10+1/2(1-2sin^10)+1/4
=1/2+1/4
=3/4。
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