Write the following complex number in rectangular form.   8 left parenthesis cosine 210 degrees plus i sine 210 degrees right parenthesis8(cos210°+isin210°)       Question content area bottom Part 1 The rectangular form of 8 left parenthesis cosine 210 degrees plus i sine 210 degrees right parenthesis8(cos210°+isin210°) is enter your response here. ​(Simplify your​ answer, including any radicals. Use integers or fractions for any numbers in the expression. Rationalize all denominators. Type your answer in the form a plus b ia+bi​.)