Answer:
C=14pi cm
A=49pi cm^2
Step-by-step explanation:
1) Circumference of a circle is 2piR and R=7cm
C=2pi(7)
C=14pi cm
2) Area of a circle is piR^2 and R=7cm
A=pi (7)^2
A=49pi cm^2
Given:


To find:
The exact value of cos(u-v) if both angles are in quadrant 3.
Solution:
In 3rd quadrant, cos and sin both trigonometric ratios are negative.
We have,


Now,




On further simplification, we get


Similarly,






Now,




Therefore, the value of cos (u-v) is 0.1872.
To complete the square (x+2/5)^2 it would be x^2+(4/5)x+4/25