Question

If A + 25° is an acute angles such that Sin (A + 25°)= cos 35°, find A.​

Answer 1

given: A+25 degree is an acute angle

Sin(A+25)=Cos35 (given)

solution:

Sin(A+25)=Cos35

Sin90-(A+25)=cos35

cos(A+25)=cos35

comparing both sides

A+25=35

A=10

hence value of A is 10

Note: sin (90-¤)=cos¤ [¤-represebts theta)

cos(90-¤)=sin¤

tan(90-¤)=cot¤

cot(90-¤)=tan¤

sec(90-¤)=cosec¤

cosec(90-¤)=sec¤

Answer 2

See the attachment which I attached .