Saved Bookmarks
| 1. |
Find the value of the expression: cos2(π/8) + 4cos2(π/4) – sec2(π/4) + 2tan2(π/3) + sin2(π/8)1. 52. 73. 94. 11 |
|
Answer» Correct Answer - Option 2 : 7
Given: cos2(π/8) + 4cos2(π/4) – sec2(π/4) + 2tan2(π/3) + sin2(π/8) Concept Used: cos2θ + sin2θ = 1 π = 180° Calculation: cos2(π/8) + 4cos2(π/4) – sec2(π/4) + 2tan2(π/3) + sin2(π/8) ⇒ {cos2(π/8) + sin2(π/8)} + 4cos245° – sec245° + 2tan260° ⇒ 1 + 4(1/√2)2 – (√2)2 + 2(√3)2 ⇒ 1 + 2 – 2 + 6 ⇒ 7 ∴ The value of the expression cos2(π/8) + 4cos2(π/4) – sec2(π/4) + 2tan2(π/3) + sin2(π/8) is 7. |
|