[" gribl al : "],[" i) "cos(45^(@)-A)*cos(45^(@)-B)-sin(45^(@)-A)*sin(45^(@)-B)=sin(A+B)]

Prove that: cos(45^(@)-A)cos(45^(@)-B)-sin(45^(@)-A)sin(45^(@)-B)=sin(A+B)

sin(45^@+A)sin(45^@-A)=

Prove that: i) sin(A+B)cos(A-B)-cos(A+B)sin(A-B)=sin2B ii) cos(45^(@)-A)cos(45^(@)-B)-sin(45^(@)-A)sin(45^(@)-B)=sin(A+B)

Prove that: i) sin(A+B)cos(A-B)-cos(A+B)sin(A-B)=sin2B ii) cos(45^(@)-A)cos(45^(@)-B)-sin(45^(@)-A)sin(45^(@)-B)=sin(A+B)

2sin45^(@)cos45^(@)

cos 45^(@)-sin 45^(@)=?

sin^(2)45^(@)+cos^(2)45^(@)=

Show that sin(45^@+A)cos(45^@-B)+cos(45^@+A)cos(45^@-B)=cos(A-B)

Evaluate sin45^(@)+cos45^(@)

Evaluate cos45^(@)cos30^(@)+sin45^(@)sin30^(@) .