Q. 65 (a) Solve the equation z2−6iz−12=0, giving the answers in the form x+iy, where x and y are real and exact.[3]
Identify Quadratic Equation: Given the quadratic equation z2−6iz−12=0, we can solve for z using the quadratic formula z=2a−b±b2−4ac, where a=1, b=−6i, and c=−12.
Calculate Discriminant: First, we calculate the discriminant, which is b2−4ac. In this case, it is (−6i)2−4(1)(−12).
Apply Quadratic Formula: Calculating the discriminant gives us 36i2+48. Since i2=−1, this simplifies to −36+48, which equals 12.
Simplify Solutions: Now we can apply the quadratic formula. The solutions for z are z=2×1−(−6i)±12.
Divide by 2: Simplifying the solutions for z gives us z=26i±23.
Express Solutions in Form: Dividing by 2, we get the solutions z=3i±3.
Express Solutions in Form: Dividing by 2, we get the solutions z=3i±3.We can now express the solutions in the form x+iy. Since there is no real part, x=0. The solutions are z=0+(3±3)i.