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    how do u work out what the value of 'w' is?

    e^-w = 4

    thanx
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    (Original post by wonkey)
    how do u work out what the value of 'w' is?

    e^-w = 4

    thanx
    hi,
    take ln on both sides
    u will get:
    -w=ln 4
    so, -w=2*ln 2
    so, -w=2*0.693
    so, w=-1.386
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    (Original post by prince_capri)
    hi,
    take ln on both sides
    u will get:
    -w=ln 4
    so, -w=2*ln 2
    so, -w=2*0.693
    so, w=-1.386
    hey, thanks for that.........is the * meant to be multiply?
    so say its ln8.....can i turn that into 2ln4?
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    ln 8 does not equal 2ln 4.

    ln 8 = ln (2^3)

    There's a log law that says ln (a^n) = nln a

    Therefore, ln 8 = 3ln 2.
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    (Original post by Nylex)
    ln 8 does not equal 2ln 4.

    ln 8 = ln (2^3)

    There's a log law that says ln (a^n) = nln a

    Therefore, ln 8 = 3ln 2.

    ah i get it, thank u!
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    (Original post by wonkey)
    hey, thanks for that.........is the * meant to be multiply?
    so say its ln8.....can i turn that into 2ln4?
    * is meant for multiply
    But ln 8 is not equal to 2*ln 4
    the reason is that ln 8=ln 2^3, and so its equal to 3*ln 2

    if u r unable to understand this part, i suggest that u have a quick read thru ln rules..and u will find the answer.
    All the best
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    how do you go about working out 'z':

    cosz + sinz = 1/3

    thank u
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    if u square both sides, u will get:

    cos^2 z + 2sin z cos z + sin^2 z = 1/9

    and u can use the identities to get:

    1 + sin 2z = 1/9

    thus sin 2z = -8/9 and so on.
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    (Original post by 4Ed)
    if u square both sides, u will get:

    cos^2 z + 2sin z cos z + sin^2 z = 1/9

    and u can use the identities to get:

    1 + sin 2z = 1/9

    thus sin 2z = -8/9 and so on.

    thanks
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    Good evening Gentlemen, I believe your question is concerning the involvement of ‘R’ and ‘∂ (alpha)’.

    Furthermore by using the above method the answers I obtained were -31.4, 121.4, 328.6........

    Please post a reply to view the method by which the answers where generated - RBG
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    2*ln2 is not the same as 2ln2
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    (Original post by Bhaal85)
    2*ln2 is not the same as 2ln2
    Doesn't that give ln4?
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    (Original post by Bhaal85)
    2*ln2 is not the same as 2ln2
    What? Of course it is, the multiplication operator is implied in 2ln2.
 
 
 
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