Question #b3d2c

2 Answers
Jul 10, 2017

If Question is

#sin2x=sin60cos30-cos60-sin30#

#=>sin2x=sqrt3/2xxsqrt3/2-1/2-1/2#

#=>sin2x=3/4-1=-1/4#

#=>2x=sin^-1(-1/4)#

#=>2x=-14.48^@#

#=>x=-14.48^@/2=-7.24^@#

Jul 11, 2017

Answer:

#x = - 7^@24 + k180^@#
#x = 97^@24 + k180^@#

Explanation:

#sin 2x = 3/4 - 1/2 - 1/2 = - 1/4 #
#sin 2x = - 1/4 = - 0.25#
Calculator and unit circle give 2 solutions;
a. #2x = - 14^@48 + k360^@# --> #x = - 7^@ 24 + k180^@#
b. #2x = 180 - (-14.48) = 194^@48 + k360^@# -->
#x = 97^@24 + k180^@#