The Student Room Group

C4 Edexcel A level 22nd June 2018 Unofficial Markscheme

Scroll to see replies

Original post by Zacks121
1a) 2-9/4x-81/64x^2 b) 17.623
2a) (4-2x-y)/(x+2y-5) b) 1+√2 1-√2
3a) a=-2 b=6 c=-1 b) ln(x+3/2x+1) - 3/2x+1 c) 1/3e^3x+3/2e^2x+3e^x+X d) 3/8ln(4x^3/2+5)
4a) show b) 8/3π
5a)k=(π+8)/2 b) y=4x-2(π-9)
6) y=6/(2+tan2x)
7a) (1,1,4) b) cosx=4√21/21 c) 12√5 d) r=(9,1,8)+k(4,-6,2) e) Q=(4,8.5,5.5)
8a) 1/4xsin4x+1/16cos4x b) π^3/64+π/16


Do you think i will lose marks for not writing ln(x+3/2x+1) and writing lnx+3 - ln2x+1 instead?
Reply 21
Original post by rex2000
i agree with most but wasnt a=2 and c=1


Yeah I got 6,6,1 for a b and c forgot what order tho
Reply 22
Original post by Fogstaz
Did you use a parallelogram for vectors? I got somewhat the same answer

No I didn't use one - mine kind of looked like a cross
Reply 23
For the last question I got Pi^3/64 + Pi/4
For Q i got (2, 8.5, 5.5) i think
Original post by sgsb0y
For the last question I got Pi^3/64 + Pi/4


i only got pi^3/64, idk where people are getting the additional part from
Reply 26
Original post by Keira Larkin
Do you think i will lose marks for not writing ln(x+3/2x+1) and writing lnx+3 - ln2x+1 instead?


Nope it did not say in simplest form
Original post by eja1407
Some of my answers:
Root 310: 17.623
Y= -6/(tan2x+1)
K=6-pi/2
Y= -4x -2pi - 26
Costheta = 4root21/21
Area = 12root5
Q(-1,16,3) - although friends disagree
Pi/16(Pi^2/4 +1) oe
U integral: 3/8 ln(4x^2+5) +c

Wasn’t 3/8ln(4u^2 + 5) so 3/8ln(4x^2/3 + 5)
For the volume I got pi cubed over 64
Reply 29
Original post by Zacks121
1a) 2-9/4x-81/64x^2 b) 17.623
2a) (4-2x-y)/(x+2y-5) b) 1+√2 1-√2
3a) a=-2 b=6 c=-1 b) ln(x+3/2x+1) - 3/2x+1 c) 1/3e^3x+3/2e^2x+3e^x+X d) 3/8ln(4x^3/2+5)
4a) show b) 8/3π
5a)k=(π+8)/2 b) y=4x-2(π-9)
6) y=6/(2+tan2x)
7a) (1,1,4) b) cosx=4√21/21 c) 12√5 d) r=(9,1,8)+k(4,-6,2) e) Q=(4,8.5,5.5)
8a) 1/4xsin4x+1/16cos4x b) π^3/64+π/16


Got different answer for 3c, was like 1/3(1+e^x)3+........, can’t remember the rest
Original post by Keira Larkin
Do you think i will lose marks for not writing ln(x+3/2x+1) and writing lnx+3 - ln2x+1 instead?


It didn't say give it in its simplest form so I doubt it, it would be 1 max.
Reply 31
Original post by mightymouse1204
Wasn’t 3/8ln(4u^2 + 5) so 3/8ln(4x^2/3 + 5)


Yes, wrote the answer wrong on here
Reply 32
Original post by Lexie12
Nope it did not say in simplest form


i hope so
Original post by YungBourdier
For the volume I got pi cubed over 64


Same! So did a friend of mine!
Original post by rex2000
that rate volume question had me for a bit i was so confused why they gave us 50


needed it for the first part
Will someone please please tell me the coordinates of Q
Reply 36
did anyone get (picubed - 4pi)/64 for the last question?
Original post by Zacks121
1a) 2-9/4x-81/64x^2 b) 17.623
2a) (4-2x-y)/(x+2y-5) b) 1+√2 1-√2
3a) a=-2 b=6 c=-1 b) ln(x+3/2x+1) - 3/2x+1 c) 1/3e^3x+3/2e^2x+3e^x+X d) 3/8ln(4x^3/2+5)
4a) show b) 8/3π
5a)k=(π+8)/2 b) y=4x-2(π-9)
6) y=6/(2+tan2x)
7a) (1,1,4) b) cosx=4√21/21 c) 12√5 d) r=(9,1,8)+k(4,-6,2) e) Q=(4,8.5,5.5)
8a) 1/4xsin4x+1/16cos4x b) π^3/64+π/16


Doesn’t C=1 cos if you let X=-3 you get 13-4(-3)=C(-6+1)^2 so 25=25C
Ngl for the coordinates of Q I got lamda = -5/2
Reply 39
Noooooo forgot to replace u with x...............

Quick Reply

Latest