How do you simplify #2- \sqrt { - 245}#?

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Answer 1 · 2017-12-14T12:22:42

#2-7sqrt(5)i#

Start by factoring the value inside the radical. You need to find some factors that have exact roots.

#-245= 5xx49xx-1#

#:.#

#sqrt(5xx49xx-1)=sqrt(5)xxsqrt(49)xxsqrt(-1)#

#sqrt(5)xx7xxsqrt(-1)#

#sqrt(-1)=icolor(white)(88)# ( where #i# is the imaginary unit )

#7sqrt(5)i#

#:.#

#2-7sqrt(5)i#

This is now in complex number form.