5x^3+8x^2/3x^4-16x^2=x^2(5x+8)/x^2(3x^2-16)=5x+8/3x^2-16
lim x--->0 5x+8/3x^2-16=8/-16=-1/2
3,857:
1. 3 is located in the thousands place
2. Since 8 is bigger than 3, it's telling it to go up a number (turning 3 into a 4)
Stays the Same: 1,2,3,4
Goes Up: 5,6,7,8, etc.
So 3,857 is now rounded into 4,000