Multiplying Complex Numbers: (8 + i)(2 + 7i)
This article will explore how to multiply the complex numbers (8 + i) and (2 + 7i).
Understanding Complex Numbers
Complex numbers are numbers that can be expressed in the form a + bi, where a and b are real numbers and i is the imaginary unit, defined as the square root of -1.
The Multiplication Process
To multiply complex numbers, we use the distributive property (often referred to as FOIL for First, Outer, Inner, Last) just like we would with binomials.
Step 1: Expand the product
(8 + i)(2 + 7i) = (8 * 2) + (8 * 7i) + (i * 2) + (i * 7i)
Step 2: Simplify
= 16 + 56i + 2i + 7i²
Step 3: Substitute i² with -1
= 16 + 56i + 2i + 7(-1)
Step 4: Combine real and imaginary terms
= (16 - 7) + (56 + 2)i
Step 5: Final result
= 9 + 58i
Conclusion
Therefore, the product of the complex numbers (8 + i) and (2 + 7i) is 9 + 58i.