Question

geometrically prove that tan(90-a)=cota​

Answer 1

Step-by-step explanation:

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We know that

tan(90+a)=sin(90+a)/cos(90+a)

=sin90⋅cosa+cos90⋅sina/cos90⋅cosa−sin90⋅sina

=cosa/-sina

=−cota

Note sin90=1

,cos90=0