InterviewSolution
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InterviewSolution
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Let `z=x+i y`be a complex number where `xa n dy`are integers. Then, the area of the rectangle whose vertices are theroots of the equation `z z ^3+ z z^3=350`is48 (b)32 (c) 40(d) 80A. 48B. 32C. 40D. 80 |
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Answer» Correct Answer - A `zbarz(barz^(2) + z^(2))= 350` Putting z +iy, we have `(x^(2) + y^(2)) (x^(2) -y^(2)) = 175` `(x^(2) + y^(2)) (x^(2) -y^(2)) = 5 xx 5xx7` `x^(2)+ y^(2) = 25` `and x^(2) -y^(2) = 7` (as other combinations given non-intergral values of x and y ) `therefore x = pm 4, y = pm 3 (x,y in I)` Hence, area is `8 xx 6 = 48` sq . units |
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