The two lines of regression are 4x + 2y - 3 = 0 and 3x + 6y + 5 = 0. Find the correlation co-efficient between x and y.
A card is drawn from a well shuffled pack of playing cards. What is the probability that it is either a space or an ace or both ?
If 1, w and w2 are the cube roots of unity, prove that = w2
Multiplying and dividing numerator and denominator by w2, we get
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Since w3 = 1 and w4 = w3.w = w
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