I don't know what I am doing wrong. Please check my work.

Find all distinct roots (real or complex) of z^2+(5+3i)z+(8+15i). Using the quadratic formula, my overall eqn is (-(5+3i)+/- sqrt(16+30i - 32-60i) )/ 2. However it is not cancelling. Can someone help me?

Question

I don't know what I am doing wrong. Please check my work.

Find all distinct roots (real or complex) of z^2+(5+3i)z+(8+15i). Using the quadratic formula, my overall eqn is (-(5+3i)+/- sqrt(16+30i - 32-60i) )/ 2. However it is not cancelling. Can someone help me?

idku · Answer

$$z^2+(5+3i)z+(8+15i)$$
$$z^2+5z+3iz+8+15i$$
is this supposed to equal to zero?

idku · Answer

@ineedhelpwithmatrices

idku · Answer

I will assume it is, cuz you said "Using the quadratic formula".

idku · Answer

z^2+(5+3i)z+(8+15i) my bad leave it like this.

anonymous · Answer

haha ok, so what exactly do i go from here

idku · Answer

(-(5+3i)+/- sqrt(16+30i - 32-60i) )$$ -5-3i±\sqrt{(16+30i - 32-60i)}<-----this?$$

anonymous · Answer

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