Q. 3i⋅(3+2i)=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 numbers 3i and (3+2i).To multiply two complex numbers, we distribute the multiplication over addition, just like we would with binomials.(3i)⋅(3+2i)=3i⋅3+3i⋅2i
Calculate the products: Calculate the products.3i×3=9i (since i is the imaginary unit, it stays with the real number 3)3i×2i=6i2 (since i×i=i2, and i2=−1)
Substitute and simplify: Substitute i2 with −1 and simplify.6i2=6∗(−1)=−6 (since i2=−1)Now we combine this with the other product:9i+(−6)
Combine the products: Write the final answer in the form a+bi.The real part a is −6, and the imaginary part b is 9.So the final answer is −6+9i.
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