Engineering Solving Problems Involving Complex Vectors

AI Thread Summary
The discussion focuses on solving two problems involving complex vectors. In Problem 1, the moduli of vectors a, b, c, and d are calculated using the formula for vector modulus, yielding specific numerical results. Problem 2 involves a system of equations to find vectors a and b, with their values derived and their moduli calculated as well. The user seeks peer review for their solutions, and feedback suggests improving notation for clarity. Overall, the thread emphasizes the application of mathematical formulas to complex vector problems and the importance of precise notation.
Martin Harris
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Homework Statement
1) The following vectors are given written as complex numbers:
a = 3-2i
b= -6-4i
c= 4+ 6i
d= -4+3i
The requirements: To calculate the vectors' modulus.

2) The following system of vectors is given
3a-2b=7
-5a+6b=3i
The requirements: To find a and b as vectors, as well as to calculate their modulus.
Relevant Equations
Let the vectors be of the following type: z = a+bi, where a = real part, b = imaginary part
Hi

Here is my attempt at a solution for problems 1) and 2) that can be found within the summary.

Problem 1)
a = 3-2i
b= -6-4i
c= 4+ 6i
d= -4+3i

Now, to calculate each vector modulus, I applied the following formula:

$$\left| Vector modulus \right| = \sqrt {(a^2 + b^2) }$$
where a = real part of the vector, and b = imaginary part of the vector

By this formula, the following vector modulus, were calculated:
$$a = \sqrt {13} = 3.605551275463989$$
$$b = 2* \sqrt {13} = 7.211102550927978$$
$$c = 2*\sqrt {13} = 7.211102550927978$$
$$d = \sqrt {25} = 5$$

End of Problem 1 solution attempt

Problem 2)
The following system of vectors is given
$$3a-2b=7 (Eq1)$$
$$-5a+6b=3i (Eq2)$$

I am requested to find vectors a,b as well as to calculate their modulus

From Eq(1), $$ vector a = \frac {7a+2b} {3} Eq (3) $$
Substituting vector a with the above form in Eq 2 yields:
$$vector b = 4.375+1.125i$$ or $$vector b = \frac {35} {8} + \frac {9i} {8} $$
Now plugging back vector b in Eq (3) yields:
$$vector a = 5.25 +0.75i$$ or $$vector a = \frac {15.75} {3} + \frac {2.25i} {3} $$

Now, to calculate the vector modulus, the same formula that was used in Problem1 will be applied, hence it will yield the following vector modulus:

$$Modulus for vector a = \frac {15*\sqrt {2}} {4} = 5.303300858899107 $$
$$Modulus for vector b = 4.517327749898163 $$

End of Problem 2 solution attempt

I would be more than grateful if someone could peer-review (check my attempt).
Many thanks!
 
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It seems all right but would be more accurate to write it using root e.g.
a=\sqrt{13}
 
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Cool! Thanks for the advice, I'll follow it.
 
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