Simon T
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1.05 = (1 + i)^6
How would you do this equation?
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MarkFL
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Assuming $i$ is a variable, and not the imaginary unit, are you interested in all 6 roots, or just the reals, or just the positive reals?
Simon T
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im not too sure what you mean. Here's a screenshot of the question:
MarkFL
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Well, what does $i$ represent...an interest rate? If so, then we are only interested in the positive real root.
Simon T
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it just says solve the power equation
MarkFL
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Okay, well to get all 6 roots, I would let:
$$r=\sqrt[3]{\frac{21}{20}}$$
And write the equation as:
$$\left((1+i)^2\right)^3-r^3=0$$
Now, factor this as a difference of cubes...what do you get?
$$r=\sqrt[3]{\frac{21}{20}}$$
And write the equation as:
$$\left((1+i)^2\right)^3-r^3=0$$
Now, factor this as a difference of cubes...what do you get?