Simplify the following expressions without using a calculator.
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Trigonometric radio.
2012-05-18 4:32 am
回答 (3)
2012-05-20 4:38 am
1/cos(90-Θ)-sin(90-Θ)/tanΘ
=1/sinΘ-cosΘ/tanΘ
=1/sinΘ-cos^2Θ/sinΘ
=sin^2Θ/sinΘ
=sinΘ
=1/sinΘ-cosΘ/tanΘ
=1/sinΘ-cos^2Θ/sinΘ
=sin^2Θ/sinΘ
=sinΘ
2012-05-20 1:09 am
cos(90 - Θ)=sinΘ
sin (90 - Θ)=cosΘ
tanΘ=sinΘ/cosΘ
1/cos(90 - Θ) - sin(90 - Θ)/tanΘ
= 1/sinΘ - cosΘ/tanΘ
= 1/sinΘ - cos Θ÷sinΘ/cosΘ
=1/sinΘ - cos ΘxcosΘ/sinΘ
=1/sinΘ - cos Θ^2/sinΘ
= (1 - cos^2 Θ)/sinΘ
= sin^2 Θ/sinΘ
= sinΘ
sin (90 - Θ)=cosΘ
tanΘ=sinΘ/cosΘ
1/cos(90 - Θ) - sin(90 - Θ)/tanΘ
= 1/sinΘ - cosΘ/tanΘ
= 1/sinΘ - cos Θ÷sinΘ/cosΘ
=1/sinΘ - cos ΘxcosΘ/sinΘ
=1/sinΘ - cos Θ^2/sinΘ
= (1 - cos^2 Θ)/sinΘ
= sin^2 Θ/sinΘ
= sinΘ
參考: me
2012-05-18 4:52 am
1/cos(90 - Θ) - sin(90 - Θ)/tanΘ
= 1/sinΘ - cosΘ/tanΘ
= 1/sinΘ - cos^2 Θ/sinΘ
= (1 - cos^2 Θ)/sinΘ
= sin^2 Θ/sinΘ
= sinΘ
= 1/sinΘ - cosΘ/tanΘ
= 1/sinΘ - cos^2 Θ/sinΘ
= (1 - cos^2 Θ)/sinΘ
= sin^2 Θ/sinΘ
= sinΘ
收錄日期: 2021-04-26 19:17:34
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