If there is such a scalar function <em>f</em>, then



Integrate both sides of the first equation with respect to <em>x</em> :

Differentiate both sides with respect to <em>y</em> :


Integrate both sides with respect to <em>y</em> :

Plug this into the equation above with <em>f</em> , then differentiate both sides with respect to <em>z</em> :



Integrate both sides with respect to <em>z</em> :

So we end up with

Answer:learn your self
Step-by-step explanation:
Lol
Answer:
Sofia is correct.
Step-by-step explanation:
Mark's statement depends on the starting point. He can be correct if they started at the 0 mile, but in this case we don't know where they started. They could had started at the 12 mile and their current position after the walking would be 16 miles.
On the other hand, Sofia's statement doesn't depend on where they started. She refers to how much they walked, not to where they are after the walking. Since they stopped after 4 non-stopping miles, their displacement was exactly 4 miles. So Sofia is correct.
Answer: 
Step-by-step explanation:
According to the given information, we have
Sample size : n= 50


Since population standard deviation is unknown, so we use t-test.
Critical value for 95 percent confidence interval :

Confidence interval : 

Required 95% confidence interval : 
Hello :
the discriminat of each quadratic equation : ax²+bx+c=0 ....(a <span>≠ 0) is :
</span><span>Δ = b² -4ac
1 ) </span>Δ > 0 the equation has two reals solutions : x = (-b±√Δ)/2a
2 ) Δ = 0 : one solution : x = -b/2a
3 ) Δ <span>< 0 : no reals solutions
in this exercice : -3x²-2x+6 =0.....a = -3 b = -2 c =6
calculate : </span>Δ............................