1.

If `(x+iy)^(1//3)=a+ib, " then " (x)/(a)+(y)/(b)` equalsA. `4(a^(2)-b^(2))`B. `2(a^(2)-b^(2))`C. `2(a^(2)+b^(2))`D. None of these

Answer» Correct Answer - C
We know that `(vec(a)xxvec(b)).(vec(c )xxvec(d))=|(vec(a).vec(c),vec(a).vec(d)),(vec(b).vec(c ),vec(b).vec(d))|=|(lambda,4),(9,lambda)|=lambda^(2)-36`
Since `vec(a)xxvec(b)` and `vec(c)xxvec(d)` are prependicular so `lambda = 6`.


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