- #1
NewtonianAlch
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Homework Statement
Show that if |z| = 10 then 497 ≤ |z[itex]^{3}[/itex] + 5iz[itex]^{2}[/itex] − 3| ≤ 1503.
The Attempt at a Solution
I'm not an entirely sure how to begin this one, or if what I'm doing is correct.
If I sub in |z| = 10 into the equation; |1000 + 500i - 3| = 997 +500i
Then the modulus of that is sqrt(997[itex]^{2}[/itex]+500[itex]^{2}[/itex]) = 1115.35
497 ≤ 1115.35 ≤ 1503