Question 72710
<pre>
need help in finding out g(-2) when g(x)= sqrt 5-x + 2. 

x = -2, then substitute

    g(-2)= sqrt (5-(-2) + 2)
         = sqrt (5+2+2)
         = sqrt 9
         = 3

Another question is sqrt -36 the same as -sqrt 36. would answer still be 6i? 

            sqrt -36 is not the same as - sqrt 36
Why? sqrt (-36) = sqrt (36 * -1)
                = sqrt 36 * sqrt (-1)
                = 6 sqrt (-1)  Remember that sqrt (-1) = i
                = 6i

While - sqrt 36 = - 6




One last question: sqrt -36 divided by sqrt -9. Is answer -2? 

                  sqrt -36
                ____________
                  sqrt -9

            

                 sqrt 36 * -1)
               ________________
                 sqrt (9 * -1)



               sqrt 36 * sqrt (-1)
              ____________________
               sqrt 9 * sqrt (-1) 
              

                  6i
                ______
                  3i

                  2 * {{{cross (3i)}}}
                 ________
                   {{{cross (3i)}}}


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