Answer:
a) 
b) 
c) the points of the form (x, -x) for x≠0
Step-by-step explanation:
a)
If φ(x, y) = arctan (y/x), the vector field F = ∇φ would be
On one hand we have,
On the other hand,
So
b)
The domain of definition of F is
i.e., all the plane X-Y except the (0,0)
c)
Here we want to find all the points such that
where k is a real number other than 0.
But this means
So, all the points in the line y = -x except (0,0) are parallel to the vector field F, that is, the points (x, -x) with x≠ 0
Answer:
X = 0
Step-by-step explanation:
Answer:
56 gallons
Step-by-step explanation:
When her gas tank is full, she has x gallons in the tank.
when she went to the gas station, she had (5/8) of x gallons of gas in her tank. she added 21 gallons into her tank, then she had x gallons in her tank.
(5/8)x + 21 = x
subtract x and 21 from both sides
(5/8)x - x = -21
factor out an x from the left side
x(5/8 - 1) = -21
simplify the parenthesis
x(-3/8) = -21
multiply both sides by -8/3
x= 56 gallons
3y-20+x+13=3x+9
3y-20+x+13+2y=180
3y-7+x=3x+9
3y=2x+16
y=2/3x+16/3
5y+x=187
5(2/3x+16/3)+x=187
10/3x+80/3+x=187
13/3x=481/3
x=37
In mathematics, number with a symbol of a point, is expressed in decimal form. When they are read, the numbers after the decimal point are read digit after digit. Therefore, in word form, the number is read as: Two hundred nine point one zero six.