1. Let the quadratic function f(x) satisfy f(x+2)=f(2-x) and the sum of squares of two real roots with f(x)=0 is 10, and the image passes through (0,3), so as to find the analytical formula of f(x).

Let f(x)=ax? +bx+c, if the image passes (0,3), then c=3. That is f(x)=ax? +bx+3

There is also a function f(x+2)=f(2-x) where the symmetry axis of f(x) is x=-b/2a=2 and b=-4a can be obtained, then

f(x)=ax？ -4ax+3

The sum of the two roots of the equation is x 1? +x2？ =(x 1+x2)？ -2*x 1*x2=4？ -2*(3/a)= 10 gives a= 1.

So the analytic formula of f(x) f(x)=x? -4x+3

2. Set A has m elements and set B has n elements. Q: How many mappings are there from A to B?

The number of mappings from set a to set b is the m power of n.