`sin(A-B)=sinA cos B-cosA sinB`

Multiply sin(A+B)=sinA cosB+ cos A sinB and sin(A-B)=sinA cosB - cosA sin B

If A=B=45^(@) , then justify sin(A+B)=sinA cosB+cosA sinB.

Using the fact that sin(A+B) = sinA cosB + cosA sinB and the differentiation, obtain the sum formula for cosines.

cos(A-B)=cosAcosB+sinA sinB

If A=B=45^(@) , then justify cos(A+B)=cosA cosB-sinA sinB .

If |(cos(A+B),-sin(A+B),cos2B),(sinA,cosA, sinB),(-cosA, sinA, cosB)|=0 then the value of B is -

If |(cos(A+B),-sin(A+B),cos2B),(sinA,cosA, sinB),(-cosA, sinA, cosB)|=0 then the value of B is -

If |[cos(A+B), -sin(A+B), cos2B], [sinA, cosA, sinB], [-cosA, sinA, cosB]|=0 , then B=

Prove that: sin(A+B)+cos(A-B)=(sinA+cosA)(sinB+cosB)

Show that (1+sinA)/(cosA)+(cosB)/(1-sinB)=(2sinA-2sinB)/(sin(A-B)+cosA-cosB)