Question

if p(x)=x^2-4x+3 evaluate p(2)-p(-1)+p(1/2)

Answer 1

the answer is -31/4. .

Answer 2

Given equation is p(x) = x^2 - 4x + 3.    --------- (1)

Given p(2) - p(-1) + p(1/2)    --------------- (2)


When p(2) Then (1) becomes 

p(2) = (2)^2 - 4(2) + 3

       = 4 - 8 + 3

       = -4 + 3

      = -1.     ----------------(3)


When p(-1) Then (1) becomes

p(-1) = (-1)^2 - 4(-1) + 3

       = 1 + 4 + 3

      = 8.   --------------------------- (4)


When p(1/2) then (1) becomes

p(1/2) = (1/2)^2 - 4(1/2) + 3
  
          = 1/4 - 2 + 3

          = 5/4.     ------------------------- (5) 


Substitute (3),(4),(5) in (2), we get

p(2) - p(-1) + p(1/2) = -1 - 8 + 5/4

                             = -9 + 5/4

                             = -31/4.


Hope this helps!