Answer:
A. 17
Step-by-step explanation:
using the cosine rule (also see attached for reference):
AB² = BC² + AC² - 2·AC·BC cos C
2·AC·BC cos C = BC² + AC² - AB²
Given that AC = 18, AB = 12 and BC = 18, substituting these into the formula
2(18)(28) cos C = 28² + 18² - 12²
1008 cos C = 964
cos C = 964/1008
cos C = 0.9563
C = cos⁻¹ 0.9563
C = 16.99 ( = 17° rounded to nearest degree)
Step-by-step explanation:
a) 1.16× 10^-6
standard form should be less than 10. therefore, count decimal places from where the decimal point is located to the right until you reach a number less than 10 ....count the number of shifts in the above is 6 shifts to the right. when moving to the right, power will be negative.(-6)
1.157/1.16 ×10^-6
b) 6.79 × 10^10
67890000000....count till a number less than 10.there will be 10 shifts to the left. the 10 will be your power,(positive) since u r moving to the left exponent is positive
6.789/6.79 × 10^10
Answer:
Step-by-step explanation:
24√3
(cos Ф -cos Ф)² + (cos Ф + cos Ф)²
Firstly: (cos Ф -cos Ф)² = 0² = 0
Secondly :(cos Ф + cos Ф)² = (2cos Ф)². = 4. (cos Ф)² = 4cos² Ф
Mind you when you raise a cosine (or sin or tan...) to the n power, the n power should affect the cosine only and NOT the angle Ф