Get detailed and accurate answers to your questions on IDNLearn.com. Get step-by-step guidance for all your technical questions from our dedicated community members.
Sagot :
To find the product of the complex numbers [tex]\( (9 + 7i) \)[/tex] and [tex]\( (6 + 3i) \)[/tex], we follow these steps:
1. Distribute each term in the first complex number by each term in the second complex number:
[tex]\[ (9 + 7i)(6 + 3i) = 9 \cdot 6 + 9 \cdot 3i + 7i \cdot 6 + 7i \cdot 3i \][/tex]
2. Multiply each term:
[tex]\[ 9 \cdot 6 = 54 \][/tex]
[tex]\[ 9 \cdot 3i = 27i \][/tex]
[tex]\[ 7i \cdot 6 = 42i \][/tex]
[tex]\[ 7i \cdot 3i = 21i^2 \][/tex]
3. Combine the terms:
[tex]\[ 54 + 27i + 42i + 21i^2 \][/tex]
4. Recall that [tex]\( i^2 = -1 \)[/tex] for imaginary numbers:
[tex]\[ 21i^2 = 21(-1) = -21 \][/tex]
5. Substitute [tex]\(-21\)[/tex] for [tex]\( 21i^2 \)[/tex] and combine the real and imaginary parts:
[tex]\[ 54 + 27i + 42i - 21 \][/tex]
6. Combine the real parts:
[tex]\[ 54 - 21 = 33 \][/tex]
7. Combine the imaginary parts:
[tex]\[ 27i + 42i = 69i \][/tex]
So, combining the real and imaginary parts together, the product of the complex numbers is [tex]\( 33 + 69i \)[/tex].
Therefore, the correct answer is:
[tex]\[ \boxed{33 + 69i} \][/tex]
So, the correct choice is:
B. [tex]\(33 + 69i\)[/tex]
1. Distribute each term in the first complex number by each term in the second complex number:
[tex]\[ (9 + 7i)(6 + 3i) = 9 \cdot 6 + 9 \cdot 3i + 7i \cdot 6 + 7i \cdot 3i \][/tex]
2. Multiply each term:
[tex]\[ 9 \cdot 6 = 54 \][/tex]
[tex]\[ 9 \cdot 3i = 27i \][/tex]
[tex]\[ 7i \cdot 6 = 42i \][/tex]
[tex]\[ 7i \cdot 3i = 21i^2 \][/tex]
3. Combine the terms:
[tex]\[ 54 + 27i + 42i + 21i^2 \][/tex]
4. Recall that [tex]\( i^2 = -1 \)[/tex] for imaginary numbers:
[tex]\[ 21i^2 = 21(-1) = -21 \][/tex]
5. Substitute [tex]\(-21\)[/tex] for [tex]\( 21i^2 \)[/tex] and combine the real and imaginary parts:
[tex]\[ 54 + 27i + 42i - 21 \][/tex]
6. Combine the real parts:
[tex]\[ 54 - 21 = 33 \][/tex]
7. Combine the imaginary parts:
[tex]\[ 27i + 42i = 69i \][/tex]
So, combining the real and imaginary parts together, the product of the complex numbers is [tex]\( 33 + 69i \)[/tex].
Therefore, the correct answer is:
[tex]\[ \boxed{33 + 69i} \][/tex]
So, the correct choice is:
B. [tex]\(33 + 69i\)[/tex]
We value your participation in this forum. Keep exploring, asking questions, and sharing your insights with the community. Together, we can find the best solutions. For dependable answers, trust IDNLearn.com. Thank you for visiting, and we look forward to assisting you again.