Question

48 Points I, M, G, and N form a square on the Argand diagram. If points I, M, and G correspond to complex numbers 2+2i, 3−3i, −2−4i, respectively, then find the complex number that corresponds to point N. Find the length of the diagonal of the square IMGN.

Answer 1

• Since points I, M, G, and N form a square, we know that the diagonal IM is perpendicular to GN and has the same length as GN. Therefore, to find the complex number corresponding to point N, we can find the midpoint of the diagonal IM and then rotate it 90 degrees counterclockwise to get the corresponding point N.

• The midpoint of IM is (2+3)/2 + (2−3)/2 i = 5/2 − 1/2 i. To rotate this point counterclockwise by 90 degrees, we can swap the real and imaginary parts and negate the new real part. This gives us the complex number −1/2 + 5/2 i, which corresponds to point N.

• To find the length of the diagonal IMGN, we can first find the length of the side of the square. The side length is the distance between I and M, which is |3−2i−2−2i| = |1−4i| = sqrt(1^2+4^2) = sqrt(17).

• The diagonal IMGN is the hypotenuse of a right triangle with sides of length sqrt(17), so we can use the Pythagorean theorem to find its length:

• |IMGN| = sqrt(2)*|IM| = sqrt(2)*sqrt(17) = sqrt(34).

Therefore, the complex number corresponding to point N is −1/2 + 5/2 i, and the length of the diagonal IMGN is sqrt(34).

Answer 2

Answer: Point N: -3+i

Diagonal length: sqrt52

Explanation:

You can start by finding point N by graphing all the other solutions on an x-y graph, using a+bi. Where a=the x point, b= the y point. After looking at this you can deduct that point N has to be at -3+i. Because the x between I and M is 1, the distance between G and N has to be 1 too. Repeat with Y.

Next, you use Points N and M to find the distance. You use the same concept that a=x, and b=y and plug this into the distance formula. You would get sqrt(-3-3)^2+(1+3)^2. This evaluates to sqrt52.