Triangle formed by rotating a complex number: area, side or argument
This type of question, asked 5 times: 2021 Paper 7, 2021 Paper 10, 26 Jul 2022, 11 Apr 2023, 28 Jan 2025. All 5 questions below, oldest first.
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Question 1
2021 Paper 7
73
The area of the triangle with vertices A(z),B(iz) and C(z+iz) is :
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Question 2
2021 Paper 10
70
Let a complex number be w=1−3i. Let another complex number z be such that ∣zw∣=1 and arg(z)−arg(w)=2π. Then the area of the triangle with vertices origin, z and w is equal to:
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Question 3
26 Jul 2022
62
Let O be the origin and A be the point z1=1+2i. If B is the point z2,Re(z2)<0, such that OAB is a right- angled isosceles triangle with OB as hypotenuse, then which of the following is NOT true?
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Question 4
11 Apr 2023
68
Let w1 be the point obtained by the rotation of z1=5+4i about the origin through a right angle in the anticlockwise direction, and w2 be the point obtained by the rotation of z2=3+5i about the origin through a right angle in the clockwise direction. Then the principal argument of w1−w2 is equal to
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Question 5
28 Jan 2025
68
Let O be the origin, the point A be z1=3+22i, the point B(z2) be such that 3∣z2∣=∣z1∣ and arg(z2)=arg(z1)+6π. Then