The key idea is that, if a vector field is conservative, then it has curl 0. Equivalently, if the curl is not 0, then the field is not conservative. But if we find that the curl is 0, that on its own doesn't mean the field is conservative.
1.

We want to find
such that
. This means



so
is conservative.
2.

Then




so
is conservative.
3.

so
is not conservative.
4.

Then




so
is conservative.
Answer: the box contained 9 square chocolates and 15 round chocolates.
Step-by-step explanation:
Let x represent the number of square chocolates contained in the box.
Let y represent the number of round chocolates contained in the box.
The box of chocolates contains square chocolates, which weigh 10g each and round chocolates which weigh 8g each. The combined weight of all the chocolates is 210g. It means that
10x + 8y = 210- - - - - - - - - - -1
The number of round chocolates is 3 less than twice the number of square chocolates. It means that
y = 2x - 3
Substituting y = 2x - 3 into equation 1, it becomes
10x + 8(2x - 3) = 210
10x + 16x - 24 = 210
26x = 210 + 24
26x = 234
x = 234/26
x = 9
y = 2x - 3 = 2 × 9 - 3
y = 18 - 3
y = 15
Answer:
y= 6
Step-by-step explanation:
A horizontal line means y = something ( the x value will change, but y remains the same)
In this case, the y value is 6
y= 6