NECO Past Questions and Answers - Page 148

736.

The lengths of the sides of a triangle are 15m, 21m, and 28cm. What is the size of the angle facing the side 21m (correct to one decimal place)?

A.

85.7°

B.

47.5°

C.

41.4°

D.

38.2°

Correct answer is B

using cosine rule,

\(cos\theta\) = \(\frac{28^2 + 15^2 - 21^2}{2\times28\times15}\)

= \(\frac{568}{840}\)

\(\theta = cos^{-1}\)

= 47.5°

737.

If sin θ = 4/5 where 0° ∠ θ ∠ 900, what is the value of cos θ + tan θ?

A.

\(\frac{14}{15}\)

B.

\(\frac{29}{15}\)

C.

\(\frac{13}{8}\)

D.

\(\frac{144}{15}\)

E.

\(\frac{24}{5}\)

Correct answer is B

No explanation has been provided for this answer.

738.

Evaluate (\(\frac{1}{343}\))\(^{\frac{1}{3}}\) + (64)\(^{-\frac{1}{3}}\) - \(\frac{4}{9}\)\(^{-\frac{1}{2}}\)

A.

-\(\frac{17}{36}\)

B.

-\(\frac{3}{28}\)

C.

\(\frac{31}{28}\)

D.

\(\frac{17}{36}\)

E.

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

Correct answer is C

(\(\frac{1}{343}\))\(^{\frac{1}{3}}\) + (64)\(^{-\frac{1}{3}}\) - \(\frac{4}{9}\)\(^{-\frac{1}{2}}\)

where \(343 = 7^3,  64 = 2^6,  4 = 2^2,  9 = 3^2\)

\(7^{-3}\) \(^{\frac{1}{3}}\) + \(2^6\) \(^{\frac{-1}{3}}\) - \(\frac{2^2}{3^2}\) \(^{\frac{-1}{2}}\) 

\(7^{-1} + 2^{-2} - (\frac{2}{3})^{-1}\)

\(\frac{1}{7} + \frac{1}{4} - \frac{3}{2}\)

\(\frac{4+7-42}{28}\)

\(\frac{31}{28}\)

739.

Solve the equation x2 - 3x - 10 = 0

A.

-2 or -5

B.

-3 or -10

C.

5 or -2

D.

2 or 5

E.

3 or 10

Correct answer is C

No explanation has been provided for this answer.

740.

Convert 101.0112 to base 10

A.

63

B.

43

C.

10

D.

\(\frac{77}{8}\)

E.

\(\frac{53}{8}\)

Correct answer is E

No explanation has been provided for this answer.