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It used to be very simple here. Next to the question box, there was something called a 'drop down menu'. From there, you categorized it into the section of questions that was relevant. However, I do not see a drop down menu anywhere in order to do that. So, how do I categorize my questions. Can't believe something so ******* simple is now obsolete.

I have numbers in 2 arrays, say:

array1 = [1,2,3,4,5,6,7.......]

array2 = [1,2,3,4,5,6,7.......]

I defined a function that should take in corresponding values in these arrays, say (1,1), (2,2), (3,3), etc. and should output and store in a new array with its own unique values, say:

array3 = [10,20,30,40.......]

However, the code keeps producing an error 'only size-1 arrays can be converted to Python scalars.'

More specifically, I am trying to get arrays with air temperature and relative humidity inputs (array1 and array2) to produce a new array that stores the dew point temperature (array3).

I'm clueless and lost on this one.

Convert 2 K/hr to F/s.

Ok, so I set up dimensional analysis, but I can't seem to find my mistake.

(2 K/hr) * (1 C / 1 K) = (2 C/hr) since a degree in K = a degree in C, and

1.8 C = 1 F or rather 1.8 Celsius is equal to one mark in Fahrenheit by the formula

F= (9/5 C ) + 32

So,

(2 C/hr) * (1 F / 1.8 C) * (1 hr/ 60 min) * (1 min / 60 s) = about 3.09*10^-4 F/s

However, the book says the answer is 0.001 F/s. 

What did I do wrong?

Can only seem to find them on Amazon or University bookstores. Any chain or locale will do.

Find the equation of the surface consisting of all points P such that the distance of P to (0,0,2) is twice the distance of P to the xy-plane.

Well, I used the distance formula both times.

Let P = (x,y,z)

distance of P to (0,0,2) = D1 = 2*D2 sqrt( (x-0)^2  + (y-0)^2  (z-2)^2 )

distance of P to xy plane = D2 = sqrt( ………..)?

Do I assume to pick a point on the xy-plane such as (1,1,0) to equate D2 to D1?

When I attempted I used a variable point, (x2,y2,z2) for the D2 equation, but it didn't work.

Convert r = cosθ + sinθ   and r = 2cosθ to cartesian equations. They are supposed to be circles. 

I know x = rcosθ and y = rsinθ and x^2 + y^2 = r^2, but 

(cosθ + sinθ)^2 = r^2 =  x^2 + y^2 

which is cos^2(θ) + 2cos(θ)sin(θ) + sin^2(θ) = x^2 + y^2

cos^2 + sin^2 = 1, so 2cos(θ)sin(θ) = x^2 + y^2

But from there, I'm clueless as to how to produce a circle in cartesian form

Find the sum of the series

Σ(n = 1 to n = ♾) of ((-1)^(n+1)) / (n^5)

to four decimal places.

I'm a bit puzzled as to the procedure. Do I use the Alternating Series Estimation Theorem, or Taylor's Inequality? The book couldn't be more confusing as to what you are supposed to do regarding Taylor's Inequality, so I try to avoid it.

As for my answer, I got 0.9721 from the first 6 terms to get accuracy to within 4 decimal places.

Σ(n=1 to infinity) of ( cos(3n))  / (1 + (1.2^n))

Let f(x) = (8+8x) / (x)

Find the general formula for the nth derivative of the Taylor series Σ(n = 0 to infinity) centered at x = 1

What I mean is the portion of the answer that asks for (f^(n) (1)) / n! when evaluating Taylor or McLaurin series, not the term carrying (x-a)^n.

The first numerator term coefficient is 16, which does not adhere to the pattern. However the successive coefficients do follow the pattern. Second coefficient is -8, then 16, then -48,192, and so on. I believed that the multiplier is 

changing by ((-1)^n) * (8(n+1)), but the formula isn't working.

In the end I imagine the sum of the series to look something like 16 + Σ(n=0 to infinity) (((-1^n) * (8(n+1))/n!) * (x-1)^n, but obviously my formula for the nth derivative doesn't work. That's what I am looking for.

How about intervertebral discs? From what I read, a lot of back pain originates from degradation of the discs and corresponding arthritis. Transplanting one would be pretty cool and could altogether eliminate back issues!

Write the function f(x) = x^0.5 as a power series: Sum from n=0 to infinity of

Cn((x-2)^n).

Cn is the coefficient of the term.

Tried writing it as sum of geometric series (1/(1-(x^0.5)) but it didn't work. Not sure what I am doing wrong.

A block of mass 5 kg is on an incline of 30 degrees whose surface has a coefficient of kinetic friction of 0.28. This block is connected to a frictionless pulley at the top of the incline, which is in turn connected to another block of mass 3kg hanging vertically from the pulley. What is the acceleration of the blocks?

Keep getting 1.23 m/s^2, but MasteringPhysics is saying no.

A box sliding on the floor with an initial velocity v0 comes to rest after traveling 8 meters. What is v0 if the coefficient of kinetic friction between the box and the floors is 0.10?

Unsure of how to make the connection between kinematic equations and the information given.

You pull a block with mass 55kg with a tension force of 350N. The coefficient of kinetic friction between the ground and sled is 0.15. However, there is also a 5 kg box on the sled and after a bit, starts sliding on the block. The coefficient of kinetic friction between the block and box is 0.30.

What is the magnitude of acceleration of the box?

Additionally, the moment the box starts sliding, the block was moving at 5 m/s. What was the box's speed after 4 m?

Do you determine whether a SEQUENCE is convergent or divergent strictly by determining its limit towards infinity?

The process of finding limits for these sequences appears to make it so.

As for a series, do you always have to determine whether it is convergent or divergent first, and then find the limit of its sums to infinity?

Just trying to solidify my understanding of the procedure and learn it. A list of tests/steps would be useful in determining values of these series that are convergent.

A ball is dropped from a height of 18 feet and bounces. Suppose that each bounce is 1/2 of the height of the bounce before.

Find an expression for the total vertical distance the ball has traveled when it hits the floor for the nth time.

Apparently an infinite series problem.

My solution was 18 + (2)(18)(1/2)^n, but it didn t work.

The ball drops the first time 18 feet. Every successive time it travels 2*18*(1/2)^n feet. So I can't come to any other conclusion that other than the answer is Distance vertically traveled = 18 + 2*18*(1/2)^n

Prove your assertion.

Gun violence or fentanyl violence?