If secA + tanA = 3, then cosA is equal to:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e.
Given that
If secA + tanA = 3 ........(1
As we know that
secA - tanA = 1/(secA + tanA)
Calculation
secA - tanA = 1/3 ........(2
Adding Equation 1 and Equation 2
2 secA = 3 + 1/3 = 10/3
sec A = 5/3
Hence, cos A = 1/sec A = 1/(5/3) = 3/5