The Student Room Group

Edexcel Core 3 - 21st June 2016 AM

Scroll to see replies

Reply 620
what proofs can be asked in this exam??
Original post by minjinoor
i would hope so! it seems to make more sense as well :s-smilie:


As long as your mathematics is correct.
Original post by Zacken
You don't, it's just there to make sure you don't get log(negative number).


Ah okay :smile: It still refers to what the domain is though right? so if k = 3/2, then the domain would be x > -3/2?
Original post by Don Pedro K.
Ah okay :smile: It still refers to what the domain is though right? so if k = 3/2, then the domain would be x > -3/2?


Is there any specific type of question that is likely to come that hasn't come in a few years( Probably the questions similar to june 2013)
another identities NOT on formula booklet but can be derived easily anyway: (^ means squared)

sin2a = 2sinacosa

cos2a = 2cos^ - 1 , 1 - sin^a , cos^a - sin^a

tan2a = 2tana / 1 - tan^a

sec^a = tan^a + 1

cosec^a = cot^a + 1

????

also, any trig differentials not in formula booklet?
Original post by Don Pedro K.
Ah okay :smile: It still refers to what the domain is though right? so if k = 3/2, then the domain would be x > -3/2?


Is there any specific type of question that is likely to come that hasn't come in a few years( Probably the questions similar to June 2013)
@Zacken In regards to iterative formula questions, If we were asked to use a suitable value for calculating x1 etc. how would you go about it?
do we need to know mapping diagrams? seems straightforward but never seen it in any papers


you just worked out t (time), you're being asked to work out T (temperature) so use your value for time in the given eqn.
Original post by minjinoor
another identities NOT on formula booklet but can be derived easily anyway: (^ means squared)

sin2a = 2sinacosa

cos2a = 2cos^ - 1 , 1 - sin^a , cos^a - sin^a

tan2a = 2tana / 1 - tan^a

sec^a = tan^a + 1

cosec^a = cot^a + 1

????

also, any trig differentials not in formula booklet?

yeah these two,
Sin(x) -> Cos(x)
Cos(x) -> -Sin(x)
Reply 631
When you used a CAST diagram for trig with the arrows is that sufficient evidence for the method marks if you get the right answers? Or do you have to show like a+180 etc like in the mark schemes?
oh yh general formula for solving for solutions ( cv is calculator value ) :

for sin:
cv + 360n
(180-cv) + 360n

for cos:
+/- cv + 360n

for tan:
cv + 180n


n being as many times as you can get solutions within the range!

i literally didn't realise these had to be applied till before my c3 mocks
does anyone know what an A* normally is?
Original post by minjinoor
oh yh general formula for solving for solutions ( cv is calculator value ) :

for sin:
cv + 360n
(180-cv) + 360n

for cos:
+/- cv + 360n

for tan:
cv + 180n


n being as many times as you can get solutions within the range!

i literally didn't realise these had to be applied till before my c3 mocks


Or use CAST diagrams if that is your thing :wink:
Original post by Dentist16
does anyone know what an A* normally is?


If you're talking about in terms of raw marks, look at grade boundaries in the past.

If you're asking about how to get an A*, it's 180 UMS or more from C3 and C4 combined plus 480 or more across all 6 units.
The people who are aiming for full ums (i need 95) are you guys usually getting 100% on the soloman papers?

I got 70/75 on paper j and just wondering if i should be capping it at this stage?
Can anyone help with this question pls:




I don't know where I'm supposed to be substituting 1.2 + 1.3

I've done f(1.2) = 4/sin(1.2) - 4(1.2) +1

and the same for f(1.3)

But I'm getting a weird answer. )':
Original post by SeanFM
Or use CAST diagrams if that is your thing :wink:


oh gosh just looked it up :o:wtf: don't think i could change my method to that 1 day before exam
Original post by SeanFM
If you're talking about in terms of raw marks, look at grade boundaries in the past.

If you're asking about how to get an A*, it's 180 UMS or more from C3 and C4 combined plus 480 or more across all 6 units.

I meant raw marks sorry, I downloaded some mark converter thing on the Edexcel website but I can't figure out how to use it, what do you use to convert your raw marks to UMS?

Quick Reply