How do you solve 4sinxcosx=1?

1 Answer
Nghi N. · mason m · Nghi N
Jul 6, 2015

x=pi/12+kpi,
x = (5pi)/12+kpi

Explanation:

Use the trig identity:
sin 2x = 2sin xcos x
In this case,
4sin xcos x = 2sin 2x = 1 =>
sin 2x = 1/2
Trig table and unit circle give 2 solutions:
a. 2x=pi/6 + 2kpi -->
x=pi/12 + kpi.
b. 2x=(5pi)/6 + 2kpi, -->
x=(5pi)/12 + kpi.

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