So with the January results just published, I thought that now was about the time to create a general revision thread leading up to this exam where we can all help each other out. Please feel free to discuss anything about AQA C4 here.
Hmm, I'm resitting this exam. I need 80 UMS for the A*, so I'll probably just look over vectors in June. Hopefully the paper will be easier than that pile of **** we got given in January.
Rsin(x+a) is the same as Rsinxcosa + Rcosxsina right? So make that equal 2sinx + 5cosx you the the sinx cancel on one side and cosx on the other, leaving you with Rcosa = 2, and Rsina = 5 Square both the equations then add them, giving R^2(cos^2a) + R^2(sin^2a)= 4 + 25 Take R^2 factor out >> R^2(cos^2a + sin^2a) = 29 sin^2 + cos^2 = 1 right? so R^2 = 29 R is the maximum value because you've stretched the curve in the y direction by R so the maximum value is root29
Does anyone have the Jan13 paper? If someone could email it me that'd be great [email protected] Only Need to get 82 UMS in this exam for the A*, but of course we all want that precious 100%