Answer:
60
Step-by-step explanation:
The least common multiple of 2 and 20 is 20.
The only factor that is shared with 20 and 3 is 1. Therefore, the least common multiple will have to be 20*3, which is 60.
<u />
Answer:
Identity is verified.
Step-by-step explanation:
We have to verify the identity 
To prove any identity we always prove one side(either left hand side or right hand side) of the equation equal to the other side.
In this identity we take the left hand side first

(as we know cos(a+b) = cosa×cosb-sina×sinb)


= - sinx ( Right hand side)
Hence identity is proved.
Answer:
(2,5)
Step-by-step explanation:
Answer:
(31)2 is the answer to (62)4
Step-by-step explanation:
Answer:
4: 3
Step-by-step explanation:
In this case, we have that there is a relationship between width and height, which is 16: 9, which means that any screen that has the same ratio would be an identical screen.
How would we do this? it must either be raised to a power or rationalized on both sides of the ratio.
If we raise to a power, it would give very large dimensions for an HDTV, therefore, it is best to remove the square root on both sides, since it has more common values for a TV.

4: 3
Therefore, a 4: 3 screen is a good choice for an HDTV with the same ratio.