Q. 30i⋅(−7i−1)=Your answer should be a complex number in the form a+bi where a and b are real numbers.
Multiply complex numbers: Multiply the complex number 30i by each term in the complex number (−7i−1).We distribute 30i across the terms inside the parentheses.30i⋅(−7i)+30i⋅(−1)
Calculate product of 30i and −7i: Calculate the product of 30i and −7i.The product of two imaginary numbers i∗i is −1, so we have:30i×−7i=30×−7×i2=−210×−1=210
Calculate product of 30i and −1: Calculate the product of 30i and −1.Multiplying an imaginary number by a real number gives an imaginary number:30i×−1=−30i
Combine results: Combine the results from Step 2 and Step 3.We add the real part and the imaginary part to get the final complex number:210+(−30i)=210−30i
Write final answer: Write the final answer in the form a+bi.The real part a is 210, and the imaginary part b is −30.So the final answer is 210−30i.
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