Question #890e1

1 Answer
Jim G.
Nov 22, 2017

#sin15^@=1/4(sqrt6-sqrt2)#

Explanation:

#"using the "color(blue)"addition formulae for sin"#

#•color(white)(x)sin(A+-B)=sinAcosB+-cosAsinB#

#sin15^@=sin(45-30)^@#

#=sin45^@cos30^@-cos45^@sin30^@#

#=(1/sqrt2xxsqrt3/2)-(1/sqrt2xx1/2)#

#=sqrt3/(2sqrt2)-1/(2sqrt2)#

#=(sqrt3-1)/(2sqrt2)xxsqrt2/sqrt2#

#=(sqrt2(sqrt3-1))/4#

#=1/4(sqrt6-sqrt2)#

Related questions
Impact of this question
271 views around the world
You can reuse this answer
Creative Commons License