Question
If SecA + TanA = 2√2 + 9, then find the value of
Sin A + Cos A.Solution
Sec²A – Tan²A = 1 (SecA – TanA) (SecA + TanA) = 1 (SecA – TanA) (2√2 + 9) = 1 (SecA - TanA) = 1/(2√2 + 9) SecA – TanA = 9 - 2√2 ………………(i) SecA + TanA = 9 + 2√2 ……………… (ii) By solving the two equations we get, 2SecA = 18 SecA = 9 CosA = 1/9 Sin²A + Cos²A = 1 Sin²A + 1/81 = 1 Sin²A = 1 - 1/81 Sin²A = 80/81 SinA= (4√5)/9 SinA + CosA = (4√5)/9+ 1/9 SinA + CosA = (1+4√5)/9
100, 75, 59, 55, 46, 45
30, 42, 48, 54, 65, 81, 126
96, 480, 120, 360, 150, 750
412, 320, 241, 169, 106, 52
- Find the wrong number in the given number series.
226, 353, 522, 739, 990, 1341 5000, 2000, 800, 320, 128, 52.2
- Find the wrong number in the given number series.
5, 25, 30, 90, 92, 86 23Â Â Â 30Â Â Â Â 44Â Â Â Â 65Â Â Â Â Â 92Â Â Â Â Â 128
- In the given number series, find the wrong number.
81, 27, 9, 6, 1, 1/3, 1/9 12, 10, 23, 65, 265, 1289Â