OCR Core 3 - Marks question.

Hey, Core 3's on Monday and I'm doing alot of past papers.
I have a calculator(FX-911ES) Which does differentiation/integration. This calculator is allowed in exams as it doesn't perform symbolic diff/int. I'm wondering:
In the question below, I'm able to complete the whole thing only using my calculator. Of course if this came up in the exam, I'd go ahead and put it in my calculator and write the answer and some "rough" working, implying that I'd integrate then substitute limits in, etc. But realistically I'd just write the answer from my calculator.

In the past paper mark scheme (Question+mark scheme below) you're awareded M1/A1 marks, I'm curious;
If I were to simply state the answer, am I still able to get full marks? Will I get 5 marks with no working providing the answer's right?

Obviously - if this is the case, I'll do working and complete the question normally - then using my calculator to check, however after the terrible D1 paper from last month I'm just worried about time and whether simply stating the answer would be a great timesaver.

Sorry for the huge question, Henry.

Reply 1

PatrickC

definitely show the working. They don't want you to integrate and just give the answer, they want you to show you can do the process

Reply 2

yellowlight

Yeah, my calculator does that too and it's great to check after to make sure you're right, but you should only use it to check after working it out properly!

Reply 3

ujdshnjan

The question here asks for an exact answer, it's seems likely your calculator won't give it exactly I know mine doesn't - it will likely give you the decimal, which is of no use here as it is not exact. Hence it would only be useful for a checking method, but a very useful one at that!

Reply 4

Gloria1234

hey can anyone help me with this question?....its from the Jan 2011 paper

f(x)= e^2x - 3e^-2x

(i)(a) show that f'(x)>0 for all x

(b) Show that the set of values for x for which f''(x)>0 is the same as the set of values for x for which f(x)>0, and state what this set of values is.

(ii) The function g is defined for all real values of x by

g(x)= e^2x + ke^-2x
where k is a constant greater that 1. Find the range of g, giving your answer in simplified form.