# Mathematics Extension 1 Exam Predictions/Thoughts (1 Viewer)

#### Arrowshaft

##### Well-Known Member
Guys I was wondering for Q14b part iii, I proved f(x1) is negative and f(x2) is positive therefore alpha is between x1 and x2, but I forgot to prove x2 is greater than x1. However I remember in part i I explained that alpha has to be greater than k (which is x1), so could it still count?
Yeah thats what I did, i think as long as you stated the usual stuff like f(x) is continuous over the interval and there is a sign change you’re good. I think it is fine because they already provided the range that alpha lies between the two values, so you just have to show the sign change.

#### llatz_

##### New Member
What year would you guys compare this exam toooo?

#### Arrowshaft

##### Well-Known Member
What year would you guys compare this exam toooo?
2014, not hard but harder than average

#### Time&moretime

##### Active Member
Could someone put me out of my misery & tell me if my internal mark is 80 and my HSC mark is around 80 (either 55 or 56 out of 70), what would my HSC mark be? What does it scale to? In need of opinion urgently, thanking you ahead for any thoughts.

#### Arrowshaft

##### Well-Known Member
Could someone put me out of my misery & tell me if my internal mark is 80 and my HSC mark is around 80 (either 55 or 56 out of 70), what would my HSC mark be? What does it scale to? In need of opinion urgently, thanking you ahead for any thoughts.
What’s your internal rank at school, if you’re not first by how much (%) is rank 1 beating you by, and your school ranking?

#### Time&moretime

##### Active Member
I am 2nd place in Math extension 1 by 4 percent. Rural school

#### Time&moretime

##### Active Member
What’s your internal rank at school, if you’re not first by how much (%) is rank 1 beating you by, and your school ranking?
Thanking you for any thoughts.

#### Arrowshaft

##### Well-Known Member
I am 2nd place in Math extension 1 by 4 percent. Rural school
That should be e4 then

#### Solanaceae

##### New Member
Wait what. I got 15 for binomials ... must’ve messed up something! Faaaaaa
I got 15 as well haha

#### Time&moretime

##### Active Member
That should be e4 then
Thankyou for your reply. Really appreciate your opinion. I was aiming for an ATAR of 92, maybe there is still hope.

#### Idkwhattoput

##### Member
Exactly what I did

#### ruthvik

##### New Member
How do you think our test compares in difficulty to those of previous years, cuz I thought last yrs exam was apparently hard but 80 raw was needed for an E4.
71 raw would get you a 90 in that exam

#### Arrowshaft

##### Well-Known Member
71 raw would get you a 90 in that exam
I doubt it’d be a 71 raw, 71 went to an 89 in 2018, and it definitely wasn’t harder than 2018 imo.

#### InteGrand

##### Well-Known Member
$\bg_white \noindent Note that it is not generally true that if \cos A = \cos B, then \cos \left(\frac{\pi }{2}-A\right) = \cos\left(\frac{\pi}{2}-B\right).$

#### Arrowshaft

##### Well-Known Member
$\bg_white \noindent Note that it is not generally true that if \cos A = \cos B, then \cos \left(\frac{\pi }{2}-A\right) = \cos\left(\frac{\pi}{2}-B\right).$
Yeah that’s what I was thinking. I didn’t want to say anything because more than one person agreed with the same method. Thanks for clearing it up.

#### Jig

##### Member
How much marks do u guys reckon you'd lose for having k=5 for that question, for some reason i didn't realise the question said x^k and x^(k+1) and rather just saw k and k+1 and did the whole procedure correctly, but with the wrong terms or whatever lol.

#### Arrowshaft

##### Well-Known Member
How much marks do u guys reckon you'd lose for having k=5 for that question, for some reason i didn't realise the question said x^k and x^(k+1) and rather just saw k and k+1 and did the whole procedure correctly, but with the wrong terms or whatever lol.
Maybe you’ll get 2/3 because even though it was wrong, you still continued through and found the result if it WERE what the question asked

Jig

#### Arrowshaft

##### Well-Known Member
How many marks you guys reckon I’d lose for accidentally finding the primitive of the integral to be tan inverse instead of log, but still continued through to evaluate it?

#### luckystrike826

##### New Member
How many marks you guys reckon I’d lose for accidentally finding the primitive of the integral to be tan inverse instead of log, but still continued through to evaluate it?
probably 2? my teacher says error carried forward doesn't work this way because you've changed the nature of the question