3 How many quadratic polynomials are there with coefficients
3. How many quadratic polynomials are there with coefficients mod 3? For each quadratic polynomial p with coefficients mod 3, write down all the solutions of p(x) = 0.
Solution
1. 7x2+4x-3=0
7x2+7x-3x-3=0
7x(x+1)-3(x+1)=0
(7x-3)(x+1)=0
x=3/7, x=-1
The solution for the quadratic polynomial with coefficient mod 3
2. 8x2+5x-3=0
8x2+8x-3x-3=0
8x(x+1)-3(x+1)=0
x=-1, =3/8
3.9x2+6x-3=0
9x2+9x-3x-3=0
9x(x+1)-3(x+1)=0
x=-1, x=3/9
4.10x2+7x-3=0
10x2+10x-3x-3=0
10x(x+1)-3(x+1)=0
x=-1, x=3/10
In this way, number of equations can be formed in the form
(n+3)x2+nx-3=0
Hence n number of quadratic polynomials can be formed with mo 3
