Round the number 6,438,593 to the nearest 1,000
​

6,438,593

The answer would be: 6,439,000

5 or higher gets the next number to round up meaning that because of the 5 in 593 would make the 8 in the thousands place round up to 9.

Glad I could help! (:

Hello from MrBillDoesMath!

pi/2, - 3pi/2

Discussion:

The solutions of sin(t) = 1 are   (pi/2) + 2*pi*n, where n = 0, -1,1, -2,2,-3,3,   etc.

In particular, sin(pi/2) = 1 ( n = 0)  and sin(-3pi/2) -1 ( n = -1) and those argument values lie in the interval [-2pi, 2pi]

Regards,  

MrB

 P.S.  I'll be on vacation from Friday, Dec 22 to Jan 2, 2019. Have a Great New Year!