C2, C3 trig questions.

Hi,

For Edexcel C2, C3 questions sometimes they say in brackets "solutions based entirely on graphical or numerical methods are not acceptable". Can you still draw the graph of the trig function / CAST (quadrant) diagram, and base your solutions off of this?

Thank you!

Hi,

Thanks! For example, in our C2 exam on Wednesday, the first trig question involved cosine and the questions said solutions based entirely on graphical methods... not acceptable.

This was how the unofficial mark scheme did it. Obviously I drew the graph of the function and then got my solutions and subtracted 70. Is this okay?

Also, for the next trig question we had to rearrange the equation to make sin the subject and then solve for theta. I drew the graph afterwards and got my solutions from this. Obviously since I had to solve rearrange a trig equation and solve for sin would my solutions still be valid? This is how the unofficial mark scheme did it. I did it the exact same way in terms of rearranging but then drew the sin curve to obtain my solutions... Sorry for waffling!