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    HI there i was stuck on these two question because i have not learnt them so could someone please help me so i could note on how to do it

    Q1 : x^5 + 1/ x^2 , write in the form x^p + x^q , where p and q are integers


    Q2: The two curves y= 5 X 4 ^x and y=4^-x intersect at the point p
    Show that the x-coordinates of the point p is a root of the equation 4^2x=0.2


    Many thanks everyone!
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    for the first one its x to the power of 5 plus x to the power of minus 2
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    (Original post by amahmoud0129)
    HI there i was stuck on these two question because i have not learnt them so could someone please help me so i could note on how to do it

    Q1 : x^5 + 1/ x^2 , write in the form x^p + x^q , where p and q are integers


    Q2: The two curves y= 5 X 4 ^x and y=4^-x intersect at the point p
    Show that the x-coordinates of the point p is a root of the equation 4^2x=0.2


    Many thanks everyone!

    For the first one:

    1/x^2 is the same as 1* x^-2 so x^-2
    So you get x^5 + x^-2

    For b is that 5 times 4^-x ?
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    (Original post by Dinaa)
    For the first one:

    1/x^2 is the same as 1* x^-2 so x^-2
    So you get x^5 + x^-2

    For b is that 5 times 4^-x ?
    Hi y= 5 times 4^x and Y= 4 to the power -x
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    (Original post by amahmoud0129)
    Hi y= 5 times 4^x and Y= 4 to the power -x
    Since they intersect and we're looking for the x coordinate, you equal both equal equations together so the y's cancel.

    5(4^x)=4^-x

    Multiply by (4^x) obviously both sides

    5(4^x)(4^x)=(4^-x)(4^x)

    Using the indices rule:

    5(4^2x)= 4^0

    Anything to the power of 0 = 1

    5(4^2x)= 1

    Divide by 5

    4^2x = 0.2
 
 
 
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