Question

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Answer 1

task/26548510
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13. 
5tg163° /tg17° =5tg(180° -17°) /tg17° = 5*(-tg17°) /17° = - 5.
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14. 
14sin409°/sin49° = 14sin409°/sin(360°+49°) = 14sin409°/sin409°) = 14.
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15. 
5tg17°*tg107° = 5tg17°*tg(90°+17°) = 5tg17°*(-ctg17°) = -5tg17°*ctg17°= - 5.