Algebra Problem............?

If

(F/B)^(μ*cotα) = (2μ*P*cotα + 2Y)/Y

prove that

p=Y(1+(tanα)/μ)(1-(F/B)^(μ*cotα))

Thanks in advance

Comments

  • Check your question. As it is written, the first statement does not lead to the second. Here are the steps. For clarity, I'm going to say (F/B)^(μ*cotα) = Z, because it's a big messy term that appears in both statements. It won't get broken up, just moved around; it doesn't deserve more than one letter.

    (F/B)^(μ*cotα) = (2μ*P*cotα + 2Y)/Y

    Z = (2μ*P*cotα + 2Y)/Y

    ---------------------------------multiply by Y

    YZ = 2μ*P*cotα + 2Y

    ---------------------------------subtract 2Y

    YZ-2Y = 2μ*P*cotα

    ---------------------------------divide by 2μ and factor out Y

    Y(Z-2)/2μ = P*cotα

    ---------------------------------cotα = 1/tanα, so multiply by tanα

    Y(tanα)(Z-2)/2μ = P

    ---------------------------------now P is separated, as in the answer, and so is Y.

    I'm going to take a sideways step now, to show why I don't think this is soluble. In a standard proof, I'd keep manipulating this P to look like the P I'm proving. Instead, I'm going to set them equal to each other, allowing me to cancel some stuff out and boil the problem down to its simplest elements. If it really is provable, then P always equals P and these two P equivalents should cancel out to 1 = 1.

    P = Y(tanα)(Z-2)/2μ = Y(1+((tanα)/μ))(1-Z) ------ remember the Z substitution I made in the first step.

    ---------------------------------divide by Y

    (tanα)(Z-2)/2μ = (1+((tanα)/μ))(1-Z)

    ---------------------------------there aren't any binomials the same between right and left (Z-2 and Z-1 are very different animals), but the right side binomials can be multiplied together.

    (tanα)(Z-2)/2μ = 1 + (tanα)/μ - Z - Z((tanα)/μ)

    Here it looks pretty nasty. Two terms added together on the left, four terms added together on the right, that's almost impossible to cancel out. But maybe expanding Z will help us. I'm going back a step to before the binomial expansion.

    (tanα)([(F/B)^(μ*cotα)]-2)/2μ = (1+((tanα)/μ))(1-[(F/B)^(μ*cotα)])

    ---------------------------------simplify cot to 1/tan and space out some operations for clarity

    ([(F/B)^(μ/tanα)]-2) * (tanα)/2μ = (1+((tanα)/μ)) * (1-[(F/B)^(μ/tanα)])

    The trouble here is, even though Z has α and μ in it, they're in an exponent. They're not coming out of there. We can't even arrange the equation around far enough to try to simplify it with logarithms. We might as well keep calling it Z.

    I can't move the problem past this point. In my opinion it's either it's miswritten or it's insoluble.

    Edit: Dang, while I was working all this out, Michael went and worked out what the typo was. Curse him for competence!

  • (F/B)^(μ*cotα) = (2μ*P*cotα + 2Y)/Y multiply by Y/2 to get:

    (Y/2)(F/B)^(μ*cotα) = μ*P*cotα + Y, subtract Y to get:

    (Y/2)(F/B)^(μ*cotα) -Y = μ*P*cotα, factor out Y to get:

    Y[ (1/2)(F/B)^(μ*cotα) -1 ] = μ*P*cotα, divide by μ*cotα to get:

    Y[ (1/2)(F/B)^(μ*cotα) -1 ] * 1/(μ*cotα) = P, rewrite 1/(μ*cotα) as tanα /μ

    p=Y(tanα/μ)*[ (1/2)(F/B)^(μ*cotα) -1 ].

    Not quite what you asked for but this is correct.

    (what you asked for is not correct)

  • hi chum this an uncomplicated question in line with linear equations you ought to use transposition approach in this technique while a term is transfered from one section to different its sign turns into opposite answer: x+4-7x=22 =4-7x=22-x (right here x comes from the left section its sign adjustments) =4=22-x+7x(right here 7x comes from the left section its sign adjustments) =4-22=6x(same) =-18=6x x=-18/6 =-3 Bye Bye!!!!!!!!!!!!!!!!!!!!!!

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