Tính tổng tất cả các căn bậc n (n ≥ 2) của một số phức z bất kỳ z(z1 + z2 + z3) = zz1 + zz2 + zz3.

step-by-step explanation:

ddd

answer: expected value of x = 1.0

step-by-step explanation:

p(x=0) = 0.25

p(x=1) = 0.50

p(x=2) = 0.25

expected value for x = 0×0.25 + 1×0.5 + 2×0.25 = 1.0

false

step-by-step explanation:

false.   two legs of the trapezoid would be congruent, but the other two would not.   were all the legs congruent, then we'd have a square; were the 2 shorter sides congruent and the 2 longer sides also congruent, we'd have a rectangle.