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Grade 11Trigonometry

If a vector A makes an angle alpha with +ve x-axis, an angle beta with +ve y-axis, and an angle gama with +ve z-axis, then proof that: sin^alpha + sin^beta + sin^gama = 2

Profile image of Debadrita Ghosh
7 Years agoGrade 11
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1 Answer

Profile image of Aditya Gupta
7 Years ago
by the formula of direction cosines we know that cos^2alpha +cos^2beta+cos^2gamma=1
or 1-sin^2alpha+1-sin^2beta+1-sin^2gama=1
or sin^2alpha+sin^2beta+sin^2gama=2
hence proved