Find the maximum and minimum values of:
Let      Â
PutÂ
Squaring and adding, we get
             Â
               Â
             Â
             Â
∴             Â
Now,               (∵ cos x and sin x lie between -1 and 1)
     Â
 Â
        Â
         Â
    Â
Hence, Â Â Â Â max. value of {a cosx + b sinx} =Â
         Min. value of {a cosx + b sinx} = -Â
Â
         Â