Write the complex number == -1+3i in trigonometric form (sometimes called polar form). Express the angle 0 in radians, where 0≤0 <2. Do not round any intermediate computations, and round the values in your answer to the nearest hundredth. =(cos+ i sin == X S 2

Please give me a correct answer if you can. Thank you!

Need only handwritten solution only (not typed one).

use half-angle formulas to find the exact value of cos(7π/8). simplify any complex fractions if necessary.