F.3 Math Trigonometric
2009-04-28 2:05 am
1.Given that tan theta = 3/4 , find the values of sin theta and cos theta by using trigonometric identities.
回答 (2)
2009-04-28 2:35 am
✔ 最佳答案
By Drawing a right-angled triangle and letting angle ABC to be beta.ａ
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As tan beta = 3/4 = ac/bc
Therefore, ac= 3 and bc = 4
Using Pyth. Theorem, ab will be 5
Therefore, sin beta = ac/ab = 3/5
whereas cos beta = bc/ab = 4/5
大約是這樣, 希望幫到你~
2009-04-28 7:32 am
Given that
tanΘ=3/4
Let ABC is a triangle, so that
∠ABC= Θ
AC=3
BC=4
By Pythagoras' theorem,
AB=5
Hence,
sinΘ=3/5
cosΘ=4/5
Best wish you would improve in mathematics very soon!
bye bye!
tanΘ=3/4
Let ABC is a triangle, so that
∠ABC= Θ
AC=3
BC=4
By Pythagoras' theorem,
AB=5
Hence,
sinΘ=3/5
cosΘ=4/5
Best wish you would improve in mathematics very soon!
bye bye!
收錄日期: 2021-04-22 23:33:26
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