Trigonometryhard · Past Paper

Find the value of tan 6 tan 42 tan 66 tan 78.

A1
B0
C1/2
D2

✓ Correct Answer: A1

Grouping tan 6 tan 66 and tan 42 tan 78 using tan(theta)tan(60-theta)tan(60+theta) = tan(3theta) reduces this to 1.

Share this question

More from Trigonometry