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    Please explain how I'm supposed to get a correct answer for these questions with working out, thank you.
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    For 2.) Consider (a-b)^2\geq 0 as the square of any real number is greater than or equal to 0.

    For 1.) and 2.) Just start from a\geq b and see if it holds true, remember when multiplying by a negative number, you have to switch the inequality sign.
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    (Original post by Jas1947)
    Please explain how I'm supposed to get a correct answer for these questions with working out, thank you.
    For the first one; (1) remember that when you multiply inequalities by -1 on both sides, the sign flips. (2) Move the 2ab on the opposite side and you can factorise all of it into (a-b)^2\geq0 and think about what happens given a's relationship to b. (3) I'm sure you can spot what you can do to both sides there.

    For the second one; use triangles or the unit circle to work out the values of tan(\frac{3}{4}\pi) and sin(\frac{\pi}{2}) (then raise this value to the 10th power). I'm sure you can work out what log(100) is. E will obviously be something less than 1 raised to the 10th power so it goes down even more. This leaves D where you can approximate what power goes onto the 2 in order to get 10, doesn't have to be exact. Once you have all these the largest one should be obvious.

    Nothing tricky here.
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    (Original post by RDKGames)
    For the first one; (1) remember that when you multiply inequalities by -1 on both sides, the sign flips. (2) Move the 2ab on the opposite side and you can factorise all of it into (a-b)^2\geq0 and think about what happens given a's relationship to b. (3) I'm sure you can spot what you can do to both sides there.

    For the second one; use triangles or the unit circle to work out the values of tan(\frac{3}{4}\pi) and sin(\frac{\pi}{2}) (then raise this value to the 10th power). I'm sure you can work out what log(100) is. E will obviously be something less than 1 raised to the 10th power so it goes down even more. This leaves D where you can approximate what power goes onto the 2 in order to get 10, doesn't have to be exact. Once you have all these the largest one should be obvious.

    Nothing tricky here.
    For the first question , the last equation with c, if i divide bith sides by c then wouldnt I just get a≥b again?
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    (Original post by Jas1947)
    For the first question , the last equation with c, if i divide bith sides by c then wouldnt I just get a≥b again?
    Yep
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    (Original post by RDKGames)
    Yep
    So 1,2 and 3 must all be true?
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    (Original post by Jas1947)
    So 1,2 and 3 must all be true?
    By the looks of it. Have a bit more confidence, man, you already established which ones are true.
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    (Original post by RDKGames)
    By the looks of it. Have a bit more confidence, man, you already established which ones are true.
    I thought so but the answer says E which confuses me because I thought it should be H instead..
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    (Original post by Jas1947)
    I thought so but the answer says E which confuses me because I thought it should be H instead..
    If c was negative then that statement would be false, but if it's positive then it's correct. They should realistically define c as being either positive or negative.

    Edit: I misinterpreted the question (DAMN YOU 2AM), it says for any real number so c can be either negative or positive for the statement to hold true. Since it's only true for ONE of these cases rather than both, it is technically incorrect.
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    C can also be negative, which is why it's E not H


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    Thank you
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    Q2) Just work them out, what is \tan(3{\pi}/4) etc. (think of the graphs). You should know the standard trig answers e.g. \sin({\pi}/2) or \mathrm{arcsin}(\dfrac{1}{2}) also you should know how to workout logs as well, e.g. the standard approach I use is that the base, in the examples' case 10, what power of 10 gives me the inside of the bracket? well 10^2 = 100 so \log_{10}(100)=2
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    For Q2: Well, what are your thoughts? What have you tried? C'mon, show some effort.
 
 
 
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