Author | Maths and Physics (Problems) |

Yes, when it was 9 year ago, coefficient are very easy.
But now, Don't even have a clue what does coefficient means
may be the digit in front of x^70, but still no clue to get this.
Oh! BTW, you are correct in reverse engineering.
at laest take 7n and paid 8n
where n may be any natural number. |

*100%*
all natural number is divisible by 5 as long as it allow decimal :P
Wow
We got a maths genius here. |

Haha okay I see :) |

+ |

To make 7 even in one step - you could draw a line between the two open ends of the 7 to turn it into the number 6 |

Nah well it's a good and valid solution ;)
Nice try though.
Okay I'll disclose the answer in a few hours if no more tries :) |

*I am an odd number. Take away one letter and I become even. What number am I? *
Alternative solution:
Start with "9". Remove the vertical line. This would be removing the letter "I". Now you have a small circle left that resembles "0".
*Or better, Make 7 even by just 1 step. And please, don't mess with the "s" :P *
The word "step" is not well defined so it makes it a very easy problem. I start with 7 and step up to 8. It is now even. :) |

Well alright, though I was looking for this solution -
7! (7 factorial) ;) |

Unanswered question -
Find the coefficient of x^70 in (x-1)(x^2 -2)(x^3 -3)(x^4 - 4)...(x^12 - 12). Challenge from my side is to do this within 2 minutes, that is the approx time it took me.
:) |

+ |

*Find the coefficient...*
I suppose the answer to post 29 is 16. I tried to solve it in my head first but it became too messy. |

Real life physics question:
You were going to cool a 1 liter bottle of Coca Cola in your freezer but you forgot it there overnight and woke up longing for it. It is now -18C. You know that the hot water in your tap is about 60C. You place the Coke in the sink and heat it with the hot tap water. How much hot water is needed if you want both the water and the Coke to reach 4C after a while? |

that is a question from your real life STB ?? |

* I suppose the answer to post 29 is 16. I tried to solve it in my head first but it became too messy. *
Nah that's wrong ;) And well as I said, it's easier than it looks :)
#32 - Well I don't really know the exact details of thermal questions (if this is one), but I just used this formula that I thought would be appropriate for equilibrium. I probably made it up XD
1*(-18) + x*(60) = (1+x)*(4)
Solving, we get x = 11/28 L. Is that close? XD |

*Real life physics question:*
You were going to cool a 1 liter bottle of Coca Cola in your freezer but you forgot it there overnight and woke up longing for it. It is now -18C. You know that the hot water in your tap is about 60C. You place the Coke in the sink and heat it with the hot tap water. How much hot water is needed if you want both the water and the Coke to reach 4C after a while?
dont think it is possible to solve that
heat gain=heat lost
so m*c*heat change=m*c*heat change
but we do not have c for cola.. s |

Treat coca-cola as frozen water ( normal water )
This is what we were told to do in questions in my Coaching, can't solve this as it was taught in 11th and I don't remember the specific heat of substances, they come in questions:p |

for Lord spiral-doom:
and not only this, you need to consider change of ice->water also (latent heat of fusion) |

well until 0C, it will be .39 litres (of water)... then to reach a thermal equilibrium of 4C, the system of coke must keep taking heat from water
one more thing, water's anomolous in the 0-4C, quite hard to imply that for precise calculations... if anyone knows what the mass will be when the system continues to take heat from the water bath after 0C
im sure im missing something crucial here |

nevermind 0.39l..this was computed with delta T ranging from -18C to 4C
he said that .39 isnt correct...im definitely missing something or this has to do with the 0-4C anomaly |

OH well I got 0.39 too, but that was an absolutely ridiculous solution anyways.
Mates I need help with this question, please help if possible, thanks.
Sorry for posting link, it's a safe link, just a screenshot of the question.
http://prntscr.com/6kcuiw
Thanks!
Currently pending questions -
#29, #32, #40 |