📘 algebra, trigonometry, geometry

1.1 Consider the arithmetic sequence: 10; 7; 4; 1; ... 1.1.1 To find the general term $T_n$ of the sequence, use the formula for an arithmetic sequence:

1.1.1 Show that equation of $f(x)$: Given points $B(-5,0)$ and $C(1,0)$ are roots of $f(x)=ax^2+bx+c$.