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A2 Maths: Core 3 Proving Identity - Help watch

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    Hi

    I am reading an example Q:
    Name:  ImageUploadedByStudent Room1473529503.787035.jpg
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    How do they get from line 2 to line 3?

    I multiplied the numerator and denominator by cosxsinx and didn't get what they have on the third line :/

    Probably a minor error from me..could someone write it out to explain possibly?

    Thank you


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    (Original post by Yusufff)
    Hi

    I am reading an example Q:
    Name:  ImageUploadedByStudent Room1473529503.787035.jpg
Views: 49
Size:  100.3 KB

    How do they get from line 2 to line 3?

    I multiplied the numerator and denominator by cosxsinx and didn't get what they have on the third line :/

    Probably a minor error from me..could someone write it out to explain possibly?

    Thank you


    Posted from TSR Mobile
    Bit of a nasty one to be honest.

    Consider the numerator first. If you multiply everything by sincos, then both denominators dissapear and you get sin * sin + cos * cos = 1.

    But since you've multiplied that by that in the numerator, you also have to do so in the denominator, which gives sin + cos this time.
    • Thread Starter
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    I figured out my silly error with the help of your post - thanks so much!


    (Original post by SeanFM)
    Bit of a nasty one to be honest.

    Consider the numerator first. If you multiply everything by sincos, then both denominators dissapear and you get sin * sin + cos * cos = 1.

    But since you've multiplied that by that in the numerator, you also have to do so in the denominator, which gives sin + cos this time.



    Posted from TSR Mobile
 
 
 
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