An opaque box encloses a region of space. we can't tell what is inside the box but we can see that on all faces of the box there is a non-zero electric field pointing inward. what can we conclude about the charge enclosed within the box?

The charge must be negative

Explanation:

Hi!

The direction of the electric field of a charge depends on the sign of the charge, when it is positive, the electric field points outwards the charge but when it is negative, it points towards the charge. (As you can seen on teh attached image)

So, if on the faces of the box, the non-zero elecric field points inwards, it must mean that the total charge inside the box must be negative

we have been given a quadratic function and we need to restrict the domain such that it becomes a one to one function.

we know that vertex of this quadratic function occurs at (5,2).

further, we know that range of this function is .

if we restrict the domain of this function to either or , it will become one to one function.

let us know find its inverse.

upon interchanging x and y, we get:

let us now solve this function for y.

hence, the inverse function would be if we restrict the domain of original function to and the inverse function would be if we restrict the domain to .

i would say