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HELPPPP
Find the product of (x + (3+5i))2.

User Goms
by
4.8k points

2 Answers

4 votes

Identity used:-


\boxed{\sf (a+b)^2=a^2+b^2+2ab}

Now


\\ \sf\longmapsto (x+(3+5i))^2


\\ \sf\longmapsto x^2+2x(3+5i)+(3+5i)^2


\\ \sf\longmapsto x^2+6x+10xi+3^2+2(3)(5i)+(5i)^2

  • i^2=-1


\\ \sf\longmapsto x^2+6x+10xi+9+30i-25


\\ \sf\longmapsto x^2+6x+10xi+30i+9-25


\\ \sf\longmapsto x^2+6x+10xi+30i-16

User Ebolton
by
4.9k points
3 votes

Answer:

Use identities:

  • (a + b)² = a² + 2ab + b²
  • i² = -1

Simplify:

  • (x + (3 + 5i))² =
  • x² + 2x(3 + 5i) + (3 + 5i)² =
  • x² + 6x + 10xi + 9 + 30i - 25 =
  • x² + 6x + 10xi + 30i - 16
User Valerio Cocchi
by
4.3k points