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5 votes
Plz I can't solve this​

Plz I can't solve this​-example-1
User Safraz
by
7.0k points

1 Answer

5 votes

Answer:

3

Explanation:

w(omega) is one of the cube roots of unity,along with 1 and w^2,

where w=(-1+i√3)/2 and w^2=(-1-i√3)/2

; where i=√-1

Also, 1+w+w^2=0 .....(1)

w^3=1 .....(2)

(The above are the properties of cube roots of unity)

From question,

(1-w)(1-w^2)

=1-w^2-w+w^3

=1-(w+w^2)+1. [From ...(2)]

=1+1+1. [From ...(1)]

=3 [ANS]

User Shankara Narayana
by
7.1k points
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