What is the solution of x $$\le$$ 4, y $$\ge$$ 0 and x $$\le$$ $$-$$4, y $$\le$$ 0?

If $$\alpha$$ and $$\beta$$ are the roots of x² + x + 1 = 0, then what is $$\sum\limits_{j = 0}^3 {({\alpha ^j} + {\beta ^j})} $$ equal to?

Under which one of the following conditions will be quadratic equation x² + mx + 2 = 0 always have real roots?

If both p and q belong to the set {1, 2, 3, 4}, then how many equations of the form px² + qx + 1 = 0 will have real roots?