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Let` z= a+ ib` (where` a,b,in R` and` i = sqrt(-1)` such that `|2z+3i| = |z^(2)` identify the correct statement(s)?A. `|z|_("maximum")` is equal to `3`B. `|z|_("maximum")` is equal to `1`C. If `|z|_("maximum")` when `z=alpha + ibeta (alpha,beta in R and I = sqrt (-1) then (alpha^(3)+beta^(3))` is equal to `27`D. If `|z|_("maximum") "when" z= + iy (x,y in R "and" i = sqrt(-1) "then" (x^(2) +2y^(2))` is equal to 2` |
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Answer» Correct Answer - A::B::C::D Given `|2z+3i| = |z^(2)|` ` because |2z+3i|le2|z|+3` `implies |z|^(2)le2|z|+3` `implies 0 le|z|le 3 " "...(1)` Again `|2z+3i|ge|2|z|-3|` `implies |z|^(2)ge|2|z|-3|` `therefore |z|ge1" " …..(2)` So,(1)`nn`(2)gives `1le|z|le3` Also,`|z|_("maximum")impliesz=3i` So, `alpha=0,beta=3` `&|z|("maximum") impliesz=-i` So,`x=0, y=-1` |
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