Mathematics Question Thread

[Wales]

I think you might have missed the post I made just above yours, hidden on a new page love your work though Wales, as always

Gah D: I swear you hadn't responded yet ):

When you think you're one step ahead but you're actually 2 hours late.

[jamonwindeyer]

Gah D: I swear you hadn't responded yet ):
When you think you're one step ahead but you're actually 2 hours late.

#jamonwillnevergodown

[Wales]

#jamonwillnevergodown

Soon...Time to sharpen my 2U skills and help out more I'll catch up man...one day

[Aaron12038488]

help
Find the equation of the line through the point of intersection of 2y - 3 = 5x and x+y+1 =0 which is perpendicular to 4x+ 2y-3 = 0.
thanks

[RuiAce]

help
Find the equation of the line through the point of intersection of 2y - 3 = 5x and x+y+1 =0 which is perpendicular to 4x+ 2y-3 = 0.
thanks

Alternatively use the k method. But in all honesty, until first year linear algebra that method is a bit of a mystery and this is more intuitive

[katnisschung]

hey I'm stuck on b..
i did a and then all i could do for be was figure out that Ao and A were the same at t=0 and
A=1/2Ao e^ -5750k (probably wrong becos there are too many unknowns) haha

if anyone could show the full step by step working out that would be awesome thanks!

[RuiAce]

hey I'm stuck on b..
i did a and then all i could do for be was figure out that Ao and A were the same at t=0 and
A=1/2Ao e^ -5750k (probably wrong becos there are too many unknowns) haha

if anyone could show the full step by step working out that would be awesome thanks!

[RuiAce]

Hey guys, I'm up to graphing trigonometric functions in class right now, and I'm confused as how to sketch them when they're added? For example, how do you sketch functions like y=sinx+sin2x and, on a separate axes, and y=cosx+sinx?

Refer to post #2042 by Jamon for similar reasons

[f_tan]

can anyone help me with this question?



Thanks!

[jamonwindeyer]

can anyone help me with this question?
(Image removed from quote.)
Thanks!

Hey!! Would be happy to help, but this is a Extension 1 question. Still might be good to see though, not really that much more difficult than the 2U stuff and no new knowledge necessary, keen?

[f_tan]

Hey!! Would be happy to help, but this is a Extension 1 question. Still might be good to see though, not really that much more difficult than the 2U stuff and no new knowledge necessary, keen?

Sorry, I didn't realise! I've just figured out how to answer the question though, but thank you!

[jamonwindeyer]

Sorry, I didn't realise! I've just figured out how to answer the question though, but thank you!

Well done!! That's alright, the ones with the purple in that textbook are all Extension questions that specific question type is a good one for you to tackle as a 2U student though!

[katnisschung]

so i have no idea why i'm getting a negative... i know its not right cos its the time for decay which can't be neg
for b)
runthrough of my working out...files too big
i subbed in Q=1/5Qo
to find t cancelled out the Qo from both sides
used ln so that i could simpligy to find t and got

t=(ln1/5)/4/10^-4 (k found from previous answer)

i hope this makes sense or otherwise if someone could just post their working out...cos i got the magnitude right
just a neg??

[jamonwindeyer]

so i have no idea why i'm getting a negative... i know its not right cos its the time for decay which can't be neg
for b)
runthrough of my working out...files too big
i subbed in Q=1/5Qo
to find t cancelled out the Qo from both sides
used ln so that i could simpligy to find t and got

t=(ln1/5)/4/10^-4 (k found from previous answer)

i hope this makes sense or otherwise if someone could just post their working out...cos i got the magnitude right
just a neg??

You definitely divided by \(-k\) in that last step? Your denominator that you put into the calculator should be negative

[katnisschung]

ahaha silly me i assumed that i had already made it -k cos it already had a neg! thanks Jamon!