The value of cosec²67+sec²57-cot²33-tan²23 is 

ABC is a triangle right angled at B and AB:BC=3:4.What is sin A+ sin B+sin C equal to

Consider the following

1.cos A/(1-tan A) + sin A/(1-cot A)=sin A +cos A

2.(1-sin A-cos A)²=2(1-sin A)(1+cos A)

Which of the above identities are correct?

If p=√(1-sin x)/(1+sin x) ,q=(1-sinx)/cos x,r=cos x/(1+sin x),then which of the following is correct?

1.p=q=r

2.p²=qr

Select the correct answer

If tan A+cot A=4 then (tan²)²A+(cot ²)²A is equal to

The angle of elevation of a cloud from a point 200m above the lake is 30° and angle of depression of its reflection in the lake is 60°.

The height of the cloud is