Question

prove that sin(90-A)×cos(90-A)/tanA =1-sinsquar A​

Answer 1

Answer:

sin(90-A)=cosA

➡cos(90-A)=sinA

Now,

➡cosA.sinA/tanA

➡cosA.sinA/sinA/cosA

➡cosA.sinA×cosA/sinA

➡cos²A

We have an identity:

↪sin²A+cos²A=1

↪cos²A=1-sin²A

Therefore,

↪cos²A=1-sin²A

LHS=RHS