Question

If k sin 17° sin 43° sin 77° = cos 39°, then the value of k is​

Answer 1

Answer:

Let A = 17 degrees

60 - A = 43

60 + A = 77

so,

k sin A sin(60 - A) sin (60 + A) = cos 39

k × 1/4 sin (3A) = cos 39

k/4 sin(3 × 17) = cos (90 - 51)

k/4 sin 51 = sin 51

k/4 = 1

k = 4

Answer 2

Answer:

this is correct............................