Solve the equation 4-6coshx + 3-2sinhx = 10

dannys9696

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Can anyone help me out with this equation...?

Solve the equation 4-6coshx + 3-2sinhx = 10
Giving the answer in 4 decimal place.

Just need help getting me on my way so i can understand thanks:)
 
Can anyone help me out with this equation...?

Solve the equation 4-6coshx + 3-2sinhx = 10
Giving the answer in 4 decimal place.

Just need help getting me on my way so i can understand thanks:)
 
Solve the equation 4-6coshx + 3-2sinhx = 10
I cannot help but think that you posted the wrong form of this question.
As posted here it is:
\(\displaystyle 4-6\cosh(x)+3-2\sinh(x)=10\\6\cosh(x)+2\sinh(x)=-3\\6\dfrac{e^x+e^{-x}}{2}+2\dfrac{e^x-e^{-x}}{2}=-3\\3(e^x+e^{-x})+(e^x-e^{-x})=-3\)
 
Can anyone help me out with this equation...?

Solve the equation 4-6coshx + 3-2sinhx = 10
Giving the answer in 4 decimal place.

Just need help getting me on my way so i can understand thanks:)

If you don't want to go back to the basic definition [which I would also] and instead use the hyperbolic trig identities, you could do something like the following example [I'm not exactly sure of what you have]: Solve the equation
coshx + a sinhx = b.
Letting c=cosh(x) and s=sinh(x) this becomes
c = b - a s
Square both sides
c2 = b2 -2ab s + a2 s2
Use the hyperbolic trig idenity
c2 = 1 + s2
to get
...
Continue from there

Note that squaring to produce an answer sometimes introduces a spurious answer (especially if one is not careful) such proving not number but zero can be equal to itself. Proof is by contradiction: Suppose a and b are non-zero and equal. Then, since a=b, if we square each side,
a2 = b2
or
a2 - b2 = (a-b) (a+b) = 0
Dividing by a-b we get (the spurious solution because I was not careful)
a+b = 0
or a=-b. Now, if a=b and a=-b then both a and b must both be zero which contradicts our premise that a and b are non-zero.
 
I cannot help but think that you posted the wrong form of this question.
As posted here it is:
\(\displaystyle 4-6\cosh(x)+3-2\sinh(x)=10\\6\cosh(x)+2\sinh(x)=-3\\6\dfrac{e^x+e^{-x}}{2}+2\dfrac{e^x-e^{-x}}{2}=-3\\3(e^x+e^{-x})+(e^x-e^{-x})=-3\)

i think the equation is supposed to be 4.6coshx + 3.2sinhx = 10
thanks for the help:)
 
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