If `(sin 135^@ - cos 240^@)/(sin135^@+cos240^@)=a+sqrtb` , then `b=`​

Prove that · (cos 135^@ - cos 120^@)/(cos 135^@ +cos 120^@) = 3-2sqrt2

Find the value of (sin 135^(@) - cos 120^(@))/(sin 135^(@) + cos 120^(@))

Prove that (i) " sin " 75^(@) =((sqrt(6)+sqrt(2)))/(4) (ii) (cos 135^(@) -cos 120^(@))/(cos 135^(@) +cos 120^(@)) =(3 -2sqrt(2)) (iii) " tan " 15^(@) +" cot " 15^(@) =4

sin120^(@)cos150^(@)-cos240^(@)sin330^(@)=

sin120^(@)cos150^(@)-cos240^(@)sin330^(@)

Prove that cos120^@cos240^@-sin120^@sin240^@=1

cos A + cos (240^(@) +A)+ cos (240^(@)-A)=