In (x^4-4x^2+4), what are the coefficients of (x^3) and (x) respectively?

Correct answer: 0 and 0

The expression x^4-4x^2+4 contains only the x^4 term, the x^2 term, and the constant term 4. It has neither an x^3 term nor an x term, so the coefficient of each missing power is taken as 0. Hence, the coefficients of x^3 and x are 0 and 0 respectively. The number -4 is the coefficient of x^2, not of x or x^3. Exam tip: Write a polynomial in descending powers of x and assign coefficient 0 to every missing power.