Is y=2x^2+3 a function

Y = (2x^2)+3 is a function because when graphed, you have an even function traveling infinitely upwards. By doing the vertical line test (drawing a vertical line at any point on the function) you can see that the vertical line only intersects one point on the graph at a time, which means the equation is a function.
Yes, it is a function.

Your maths is very weak try yourself this would improve your skills don't depend on others