Question

Find m to the second power + 1/m to the second power if m+1/m = square root of 71 . WILL MARK BRAINLIEST

Answer 1

Answer:  69

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Explanation:

Note that m + 1/m and m^2 + 1/(m^2) are very similar. If we square (m + 1/m), then we end up with something in the form (a+b)^2 = a^2 + 2ab + b^2, where a = m and b = 1/m. The 2ab portion is equal to 2*m*(1/m) = 2 which allows us to isolate m^2 + 1/(m^2) fully.

The steps below show this

$m + \frac{1}{m} = \sqrt{71}\\\\\left(m + \frac{1}{m}\right)^2 = \left(\sqrt{71}\right)^2\\\\m^2 + 2*m*\frac{1}{m} + \frac{1}{m^2} = 71\\\\m^2 + 2 + \frac{1}{m^2} = 71\\\\m^2 + 2 + \frac{1}{m^2} - 2 = 71-2\\\\m^2 + \frac{1}{m^2} = 69$

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Alternatively, you can isolate m in the equation $m + \frac{1}{m} = \sqrt{71}$ to get two irrational solutions. Plug either solution into m^2 + 1/(m^2) and you should get the same result as above.