Let unknown number be x.
Given,
7x - 8 = 3x + 4
4x = 12
x = 3
Hence, the number is 3.
Answer:
cos 4u = co^s2 2u - sin^2 2u
Step-by-step explanation:
cos 4u = co^s2 2u - sin^2 2u
Let 4u = 2x
cos 2x = cos^2 x - sin^ 2 x
cos (x+x) = cos^2 x - sin^ 2 x
Using cos(x+y) = cos(x)cos(y) -sin(x)sin(y)
cos(x) cos(x)- sin(x) sin (x)= cos^2 x - sin^ 2 x
cos^2 (x) -sin^2 (x) =cos^2 x - sin^ 2 x
Since this is true
cos 2x = cos^2 x - sin^ 2 x
This is true
Substituting 4u back for 2x
cos 4u = co^s2 2u - sin^2 2u
This is true
Answer:
1900M
Step-by-step explanation:
If the athlete runs round a rectangular park, the distance covered can be determined by calculating the perimeter of the park
Perimeter of a rectangle = 2 x (length + width)
2 x (60 + 35) = 190m
Since he run rounds 10 times, the total distance covered = 190m x 10 = 1900m
