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.

271.

The tangent to the curve \(y = 4x^{3} + kx^{2} - 6x + 4\) at the point P(1, m) is parallel to the x- axis, where k and m are constants. Find the value of k

A.

3

B.

2

C.

-3

D.

-2

Correct answer is C

\(y = 4x^{3} + kx^{2} - 6x + 4\)

\(\frac{\mathrm d y}{\mathrm d x} = 12x^{2} + 2kx - 6\)

At P(1, m)

\(\frac{\mathrm d y}{\mathrm d x} = 12 + 2k - 6 = 0\) (parallel to the x- axis)

\(6 + 2k = 0 \implies k = -3\)

272.

Find the fourth term of the binomial expansion of \((x - k)^{5}\) in descending powers of x.<

A.

\(10x^{3}k^{2}\)

B.

\(5x^{3}k^{2}\)

C.

\(-5x^{2}k^{3}\)

D.

\(-10x^{2}k^{3}\)

Correct answer is D

\((x - k)^{5} = ^{5}C_{0}x^{5}(-k)^{0} + ^{5}C_{1}x^{4}(-k)^{1} + ...\)

The fourth term in the expansion = \(^{5}C_{4 - 1}(x)^{5 - 3}(-k)^{3 = 10 \times x^{2} \times -k^{3}\)

= \(-10x^{2}k^{3}\)

273.

The binary operation * is defined on the set of R, of real numbers by \(x * y = 3x + 3y - xy, \forall x, y \in R\). Determine, in terms of x, the identity element of the operation.

A.

\(\frac{2x}{x - 3}, x \neq 3\)

B.

\(\frac{2x}{x + 3}, x \neq -3\)

C.

\(\frac{3x}{x - 3}, x \neq 3\)

D.

\(\frac{3x}{x + 3}, x \neq -3\)

Correct answer is A

From the rules of binary operation, \(x * e = x\)

\(\implies x * e = 3x + 3e - xe = x\)

\(3e - xe = x - 3x = -2x\)

\(e = \frac{2x}{x - 3}, x \neq 3\)

274.

Simplify \(\frac{\tan 80° - \tan 20°}{1 + \tan 80° \tan 20°}\)

A.

\(3\sqrt{2}\)

B.

\(2\sqrt{3}\)

C.

\(\sqrt{3}\)

D.

\(\sqrt{2}\)

Correct answer is C

\(\tan (x - y) = \frac{\tan x - \tan y}{1 + \tan x \tan y}\)

\(\implies \frac{\tan 80 - \tan 20}{1 + \tan 80 \tan 20} = \tan (80 - 20) = \tan 60°\)

\(\tan 60 = \frac{\sin 60}{\cos 60} = \frac{\sqrt{3}}{2} ÷ \frac{1}{2}\)

= \(\sqrt{3}\)

275.

Simplify \(\frac{\sqrt{3}}{\sqrt{3} - 1} + \frac{\sqrt{3}}{\sqrt{3} +1}\)

A.

\(\frac{1}{2}\)

B.

\(\frac{1}{2}\sqrt{3}\)

C.

\(3\)

D.

\(2\sqrt{3}\)

Correct answer is C

\(\frac{\sqrt{3}}{\sqrt{3} - 1} + \frac{\sqrt{3}}{\sqrt{3} + 1}\)

= \(\frac{\sqrt{3}(\sqrt{3} + 1) + \sqrt{3}(\sqrt{3} - 1)}{(\sqrt{3} - 1)(\sqrt{3} + 1)}\)

= \(\frac{6}{3 - 1} \)

= 3