(a) If logo a = 1.3010 and log(_{10})b – 1.4771. find the value of ab

(b)

In the diagram. O is the centre of the circle,< ACB = 39(^o) and < CBE = 62(^o). Find: (i) the interior angle AOC;

(ii) angle BAC.

##### Explanation

(a) finding a = 10(^{1.3010}) and b = 10(^{1.4771})

Then, ab = 10(^{1.3010}) x 10(^{1.4771}) = 10(^{2.4771}) = 599.9

(b)(i) they were expected to find < ABC = 180° – 62° = 118°

Exterior < AOC a 2 x 118° – 236° (< at centre is twice angle at the circumference)

Interior < AOC = 360° – 236° = 124°(angle at a point) as required.

(b)(ii) < BAC in 180° – 39° – 118° = 23° (sum of angles of a triangle)