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Lin decides to solve the equation using the quadratic formula. Here is her work: xxx=−b±b2−4ac−−−−−−−√2a=−(−6)±(−6)2−4(1)(10)−−−−−−−−−−−−−√2(1)=6±36−40−−−−−−√2 Lin knows 36−40 is a negative number and isn't sure what to do next. Show how Lin can write her solution using i.

Respuesta :

MrRoyal

Answer:

[tex]x = 3 + i\ or\ x = 3 - i[/tex]

Step-by-step explanation:

Given

[tex]x = \frac{-(-6) \± \sqrt{(-6)^2 - 4(1)(10)}}{2*1}[/tex]

Required

Solve, in terms of i

We have:

[tex]x = \frac{-(-6) \± \sqrt{(-6)^2 - 4(1)(10)}}{2*1}[/tex]

Solve the expressions in bracket

[tex]x = \frac{-(-6) \± \sqrt{36 - 40}}{2*1}[/tex]

[tex]x = \frac{-(-6) \± \sqrt{-4}}{2}[/tex]

Express -4 as 4 * -1

[tex]x = \frac{-(-6) \± \sqrt{-4*1}}{2}[/tex]

Split

[tex]x = \frac{-(-6) \± \sqrt{4}*\sqrt{-1}}{2}[/tex]

In complex numbers;

[tex]i = \sqrt{-1[/tex]

So, we have:

[tex]x = \frac{-(-6) \± 2*i}{2}[/tex]

[tex]x = \frac{6 \± 2i}{2}[/tex]

Factorize

[tex]x = \frac{2(3 \± i)}{2}[/tex]

[tex]x = 3 \± i[/tex]

Split

[tex]x = 3 + i\ or\ x = 3 - i[/tex]