NDA2012MathematicsTrigonometric Ratios & IdentitiesActual
Let (A+B)=1 and (A-B)=1 / 2 , where A, B [0, 2 ] . What is the value A?
Options
- A6
- B3
- C4
- D8
Correct answer
B. 3
Step-by-step solution
aligned (A+B) & =1 (A+B) & = 90^ A+B & =90^ (A-B) & = 1 2 = 30^ A-B & =30^ 2 A & =120 A & =60 B & =30 aligned