Question

1. Find max (x+2,10) for the range 0<=x<=20 ?
2. Find min (x.x, 15) for the range 0<=x<=6 ?
Kindly inform the steps to be followed in such questions.

Answer 1

   maximum of two numbers :  x + 2  and  10
   in the range   0 <=  x <= 20
             2 <=  x+2  <=22        and                 10 is always fixed.

   if  x is less than 8, then  x+2 will be less than 10.
   if  x  is more than 8, then x+2  will be more than 10.

 so     Max( x+2, 10)  will be 
                       =  10  for    0 <= x <= 8
                       =  x+2  for    8 <= x  <= 20
==============

   is that  minimum of  x * x , and 15  in the range    0 <=  x  <=  6  ?
           x² < 15      for      x  < √15
           x² > 15    for    x > √15

so        minimum of  x² and 15 :  in the given range.
                 x²,      0 <= x <=  √15
                 15,      √15  <=  x   <=  6