limx→0sin5x−sin3xsinx
=limx→02cos(5x+3x2)sin(5x−3x2)sinx
[Applying Componendo & dividendo formula]
=limx→0(2cos4xsinxsinx)
=2 limx→0cos 4x
=2×cos 0=2
limx→0tanx−sinxsin3x−3sinx
limx→0sin 5xtan 3x