11/4 
Explanation:
to find the minimum value we require to find the vertex and determine if max/min
for a quadratic in standard form ; ax² + bx + c 
the coordinate of the vertex is..
 xvertex = -b/2a
x² - 3x + 5 is in standard form with a = 1,b = - 3 and c = 5 
 xvertex = - , -3/2 = 3/2
substitute this value into the equation for y-coordinate 
yvertex = ( 3/2 ) ² -3 (3/2) + 5 = 11/4
 
vertex = ( 3/2, 11/4 )
 
to determine whether max/min 
• if a > 0 then minimum u
• ifa < 0 then maximum n
 here a = 1 > 0 hence minimum 
 
minimum value of x² - 3x + 5 is 11/4
hope you understand this :)