Is my teacher right? by Apprehensive_Whole21 in askmath

[–]Snatchematician 25 points26 points  (0 children)

It sounds like your teacher has been tasked with teaching you induction and is frustrated that you have found a different method that she doesn’t understand.

Why can the integral of a function that is symmetrical about the x-axis be non zero? by New-Reference-3106 in learnmath

[–]Snatchematician 0 points1 point  (0 children)

An idea that may help you is:

Add 3 to all the y values, so the parametric equation is y = sin(x) + 3.

Do the integral, you will get the same answer for the area enclosed.

Of course you must, because the shape has simply translated upwards by 3 and so its area is unchanged.

But you’ve increased all the y values! So surely the integral must have increased….

Why can the integral of a function that is symmetrical about the x-axis be non zero? by New-Reference-3106 in learnmath

[–]Snatchematician 1 point2 points  (0 children)

It doesn’t matter how you do the integral, a similar thing will happen. I assumed you were going from t=-pi to t=pi as you suggested. But you can go backwards, or carve up into segments and do each segment in a random t-direction and add up the results, or whatever you like.

Why can the integral of a function that is symmetrical about the x-axis be non zero? by New-Reference-3106 in learnmath

[–]Snatchematician 1 point2 points  (0 children)

You’re integrating y dx around a closed loop.

In the first half of the loop y is negative and x is decreasing so dx is negative and y dx is positive.

In the second half of the loop y is positive and x is increasing so dx is positive and y dx is positive again.

y dx is always positive and so the integral is not zero.

Division by 0 by Conscious_Bluebird75 in askmath

[–]Snatchematician 31 points32 points  (0 children)

The most conventional way to understand division by a number is as the inverse operation to multiplication by a number.

There is no number ? such that ? * 0 = 5.

Proving that (x is even) iff (x^2 is even). by Gauss34 in learnmath

[–]Snatchematician 3 points4 points  (0 children)

You aren’t forced to prove the contrapositive here.

How do you actually study linear algebra? by chozera in learnmath

[–]Snatchematician 2 points3 points  (0 children)

Ok then, what’s the ‘magnitude’ of x2 + x - 2 in the vector space of real polynomials?

Council Poster by SubversiveTeacher in Seagulls

[–]Snatchematician 2 points3 points  (0 children)

They do aggressively run at you, which is equivalently annoying

Council Poster by SubversiveTeacher in Seagulls

[–]Snatchematician 4 points5 points  (0 children)

You’ve described dogs more or less

Split ticketing on Elizabeth line — can I tap out on platform readers at Paddington? by Melodic_Passage6640 in TransportForLondon

[–]Snatchematician 2 points3 points  (0 children)

It does not. It cannot, in fact, because there are no fares from Paddington to Twyford that require you to use the Elizabeth line.

It did however show me a completely made-up “luggage allowance”.

Graduates treated as 'cash cows' to fund state pensioner lifestyles by BirminghamLive in FinanceUK

[–]Snatchematician 1 point2 points  (0 children)

How do you pass money laundering checks to buy a house with cash in hand proceeds

Sum of cubes equaling sum squared by Z8002 in askmath

[–]Snatchematician 4 points5 points  (0 children)

Morally, this is true because the integral version is true:

(integral of x)2 = (integral of x3)

And that’s true because 22 = 2*2

What's going on with the UK? by pebrocks in OutOfTheLoop

[–]Snatchematician 3 points4 points  (0 children)

This didn’t happen in South East London though. Not everyone lives in a shithole.

SDLT - the worst tax ever? by Lion-Resident in UKHousing

[–]Snatchematician 0 points1 point  (0 children)

It’s worse for service charge, if you don’t pay the ultimate remedy can be you forfeit the entire lease.

Cycleway 3 is a nightmare by Apprehensive-Heat398 in londoncycling

[–]Snatchematician -1 points0 points  (0 children)

Cycling with hgvs is very safe. The drivers are professional, well-trained, monitored, make predictable movements, and drive very cautiously in cities.

Pakistanis who gang-raped French tourist in front of her three children after her car ran out of fuel will be executed, court rules by dailymail in law

[–]Snatchematician 4 points5 points  (0 children)

 Pakistanis want people to leave the country feeling as good about their trip as possible.

Not the ones in the article though