Further Mathematics questions and answers

Further Mathematics Questions and Answers

Test your knowledge of advanced level mathematics with this aptitude test. This test comprises Further Maths questions and answers from past JAMB and WAEC examinations.

536.

Find the coefficient of \(x^3\) in the binomial expansion of \((3x + 4)^4\) in ascending powers of x

A.

432

B.

194

C.

144

D.

108

Correct answer is A

\((3x + 4)^{4} = ^{4}C_{0}(3x)^{0}(4)^{4} + ^{4}C_{1}(3x)^{1}(4)^{3} + ^{4}C_{2}(3x)^{2}(4)^{2} + ^{4}C_{3}(3x)^{3}(4)^{1} + ^{4}C_{4}(3x)^{4}(4)^{0}\)

\(x^{3} = ^{4}C_{3}(3x)^{3}(4) = \frac{4!}{3!1!} \times 3^{3} \times 4\)

= \(432x^{3}\)

537.

Find the angle between \((5i + 3j)\) and \((3i - 5j)\)

A.

180°

B.

90°

C.

45°

D.

Correct answer is B

\(a . b = |a||b|\cos \theta\)

\(\cos \theta = \frac{a . b}{|a||b|}\)

= \( \frac{(5i + 3j).(3i - 5j)}{(\sqrt{5^2 + 3^2})(\sqrt{3^{2} + (-5)^{2}})}\)

= \(\frac{0}{34} = 0\)

\(\theta = \cos^{-1} 0 = 90°\)

538.

Given that \(AB = \begin{pmatrix} 4 \\ 3 \end{pmatrix}\) and \(AC = \begin{pmatrix} 2 \\ -3 \end{pmatrix}\), find |BC|.

A.

\(4\sqrt{2}\)

B.

\(6\sqrt{2}\)

C.

\(2\sqrt{10}\)

D.

\(4\sqrt{10}\)

Correct answer is C

\(BC = BA + AC\)

Given, \(AB\), then \(BA = - AB\)

= \(AB = \begin{pmatrix} 4 \\ 3 \end{pmatrix} \implies BA = \begin{pmatrix} -4 \\ -3 \end{pmatrix}\)

\(\therefore BC = \begin{pmatrix} -4 \\ -3 \end{pmatrix} + \begin{pmatrix} 2 \\ -3 \end{pmatrix}\)

= \(\begin{pmatrix} -2 \\ -6 \end{pmatrix}\)

\(|BC| = \sqrt{(-2)^{2} + (-6)^{2}} = \sqrt{40} \)

= \(2\sqrt{10}\)

539.

Integrate \((x - \frac{1}{x})^{2}\) with respect to x.

A.

\(\frac{1}{3}(x - \frac{1}{x})^{3} + c\)

B.

\(\frac{x^{3}}{3} - x\sqrt{\frac{1}{x^{3}}} + c\)

C.

\(\frac{x^{3}}{3} - 2x + \frac{1}{x^{3}} + c\)

D.

\(\frac{x^3}{3} - 2x - \frac{1}{x} + c\)

Correct answer is D

\((x - \frac{1}{x})^{2} = x^2 - 2 + \frac{1}{x^2}\)

\(\int (x^2 + \frac{1}{x^2} - 2) \mathrm {d} x\)

= \(\int (x^2 + x^{-2} - 2) \mathrm {d} x\)

= \(\frac{x^3}{3} - 2x - \frac{1}{x}\)

540.

If \(Px^{2} + (P+1)x + P = 0\) has equal roots, find the values of P.

A.

\(\text{-1 and }\frac{-1}{3}\)

B.

\(\text{1 and }\frac{-1}{3}\)

C.

\(\text{-1 and }\frac{1}{3}\)

D.

\(\text{1 and }\frac{1}{3}\)

Correct answer is B

For equal roots, \(b^{2} - 4ac = 0\)

From the equation, \(a = P, b = (P+1), c = P\)

\((P+1)^{2} - 4(P)(P) = P^{2} + 2P + 1 - 4P^{2} = 0\)

\(-3P^{2} + 2P + 1 = 0 \implies 3P^{2} - 2P - 1 = 0\)

\(3P^{2} - 3P + P - 1 = 0\)

\(3P(P - 1) + 1(P - 1) = 0\)

\(P = \text{1 or }\frac{-1}{3}\)