Q. Find all of the cube roots of −1 and write the answers in rectangular (standard) form.
Identify Equation: Identify the equation for finding cube roots of a number.To find the cube roots of −1, we solve the equation x3=−1.
Solve Real Cube Root: Solve for the real cube root.The real cube root of −1 is x=−1, because (−1)3=−1.
Find Complex Roots: Find the complex cube roots using the polar form of complex numbers.Express −1 in polar form: −1 = 1*(cos(π) + i*sin(π)).Using De Moivre's Theorem, the nth roots are given by:xk=r1/n(cos(nθ+2kπ)+isin(nθ+2kπ))for k = 0, 1, ..., n−1, where n = 3 here.
Calculate First Root: Calculate the first complex cube root (k=1).x1=11/3(cos(3π+2π)+isin(3π+2π))x1=cos(33π)+isin(33π)x1=cos(π)+isin(π)x1=−1+0i