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.

556.

Given that \(x * y = \frac{x + y}{2}, x \circ y = \frac{x^{2}}{y}\) and \((3 * b) \circ 48 = \frac{1}{3}\), find b, where b > 0.

A.

8

B.

6

C.

5

D.

4

Correct answer is C

\((x * y) = \frac{x+y}{2}\)

\((3 * b) = \frac{3+b}{2}\)

\(x \circ y = \frac{x^{2}}{y}\)

\((\frac{3+b}{2}) \circ 48 = \frac{(\frac{3+b}{2})^{2}}{48} = \frac{1}{3}\)

\(\frac{(3+b)^{2}}{48 \times 4} = \frac{1}{3}\)

\((3 + b)^{2} = \frac{48 \times 4}{3} = 64\)

\(b^{2} + 6b + 9 = 64 \implies b^{2} + 6b + 9  - 64 = 0\)

\(b^{2} + 6b - 55 = 0 \implies b^{2} - 5b + 11b - 55 = 0\)

\(b(b - 5) + 11(b - 5) = 0 \implies (b - 5) = \text{0 or (} b + 11) = 0\)

Since b > 0, b - 5 = 0 

b = 5.

557.

Given that \(3x + 4y + 6 = 0\) and \(4x - by + 3 = 0\) are perpendicular, find the value of b.

A.

4

B.

3

C.

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

D.

\(\frac{1}{4}\)

Correct answer is B

When you have two lines, \(y_{1}, y_{2}\), perpendicular to each other, the product of their slopes = -1.

\(3x + 4y + 6 = 0 \implies 4y = -6 - 3x\)

\(\therefore y = \frac{-6}{4} - \frac{3}{4}x\)

\(\frac{\mathrm d y}{\mathrm d x} = \frac{-3}{4}\)

Also, \(4x - by + 3 = 0  \implies by = 4x + 3\)

\(y = \frac{4}{b}x + \frac{3}{b}\) 

\(\frac{\mathrm d y}{\mathrm d x} = \frac{4}{b}\)

\(\frac{-3}{4} \times \frac{4}{b} = -1 \implies \frac{4}{b} = \frac{4}{3}\)

\(b = 3\)

558.

Simplify: \((1 - \sin \theta)(1 + \sin \theta)\)

A.

\(\sin^{2} \theta\)

B.

\(\sec^{2} \theta\)

C.

\(\tan^{2} \theta\)

D.

\(\cos^{2} \theta\)

Correct answer is D

\((1 + \sin \theta)(1 - \sin \theta) = 1 - \sin \theta + \sin \theta - \sin^{2} \theta\)

\(= 1 - \sin^{2} \theta\)

Recall, \(\cos^{2} \theta + \sin^{2} \theta = 1\)

\(\therefore 1 - \sin^{2} \theta = \cos^{2} \theta\).

559.

If \(\frac{1}{5^{-y}} = 25(5^{4-2y})\), find the value of y.

A.

4

B.

2

C.

-4

D.

-5

Correct answer is B

\(\frac{1}{5^{-y}} = 25(5^{4-2y})\)

\(\implies 5^{y} = (5^{2})(5^{4-2y})\)

\(5^{y} = 5^{2+4-2y}\)

Comparing bases, we have

\(y = 6 - 2y\)

\(3y = 6 \implies y = 2\)

560.

Forces of magnitude 8N and 5N act on a body as shown above. Calculate, correct to 2 dp, the angle that the resultant makes with the horizontal.

A.

80.76°

B.

75.00°

C.

71.99°

D.

15.00°

Correct answer is A

No explanation has been provided for this answer.