Ok the last question on those pages of question is this and i have got stuck and cant figure it out. I need to show that (ds=degrees)(adsbygoogle = window.adsbygoogle || []).push({});

Sin(45ds+x) +cos(45ds+x) = sqaureroot2 cosx.

Ok so i did left side first and changed it to.

Sin45Cosy + Cos45Siny +Cos45Cosy - Sin45Siny

Now what i want to do is divide out the CosY and Sin Y but even if i do that it doesnt make square root two and i dont know what to do from there. Can you help me solve this last practise question.

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# The last big toughy

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