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Question
The value of 3 sin 70° sec 20° + 2 sin 49° sec 51° is
Options
2
3
5
6
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Solution
5
Explanation;
Hint:
3 sin 70° sec 20° + 2 sin 49° sec 51°
= `(3 sin 70°)/(cos (90 - 70°)) + (2 sin 49°)/(cos (90 - 49°))`
= `3 sin 70^circ/sin 70^circ + 2 sin 49^circ/sin 49^circ`
= 3 + 2
= 5
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