Question

Evaluate cosπ\7+cos2π\7+ cos 3π\7+cos4π\7+cos5π\7+cos6π\7+cos7π\7

Answer 1

We can get the trigonometric ratios using calclator or mathematics table

cosπ\7+cos2π\7+ cos 3π\7+cos4π\7+cos5π\7+cos6π\7+cos7π\7

= 0.90 + 0.62 + 0.22 + (-0.22 - 0.62 - 0.9 - 1)

= 1.74 - 2.74

= -1



cosπ\7+cos2π\7+ cos 3π\7+cos4π\7+cos5π\7+cos6π\7+cos7π\7 = -1

Answer 2

Answer:

Step-by-step explanation:

We can get the trigonometric ratios using calclator or mathematics table

cosπ\7+cos2π\7+ cos 3π\7+cos4π\7+cos5π\7+cos6π\7+cos7π\7

= 0.90 + 0.62 + 0.22 + (-0.22 - 0.62 - 0.9 - 1)

= 1.74 - 2.74

= -1

cosπ\7+cos2π\7+ cos 3π\7+cos4π\7+cos5π\7+cos6π\7+cos7π\7 = -1