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It is known that ∠ A is an acute angle, and if Sina = cos30 °, then Tana=
From ∠ a to acute angle
sina=cos(90°-a)=cos30°
That is 90 ° - a = 30 °
a=60°
Tana = tan60 ° = radical 3
If sin α = cos 30 ° then Tan α is known to be an acute angle
sinα=cos30°
The solution is a = 60 degree
So, Tan 60 ° = root 3
The key to these questions is to remember Sina = cos (90-a)
The value of tan70 ° + tan50 ° - 3tan70 ° tan50 ° is equal to ()
A. 3B. 33C. −33D. −3
From tan120 ° = Tan (70 ° + 50 °) = tan70 ° + tan50 ° 1 − tan70 ° tan50 ° = - tan60 ° = - 3, tan70 ° + tan50 ° = - 3 + 3tan70 ° tan50 ° is obtained, then tan70 ° + tan50 ° - 3tan70 ° tan50 ° = - 3
What is (cos15 + sin15) (cos15-sin15) equal to?
Cos 15 square - Sin 15 square is equal to the root sign three
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