How do you solve #x^2-1=0#?

2 Answers
Mar 9, 2018

Answer:

#color(blue)(x=-1)# or #color(blue)(x=+1)#

Explanation:

Remember "the difference of squares"
#color(white)("XXX")a^2-b^2=(a+b)(a-b)#

Therefore
#color(white)("XXX")x^2-1=0#

#color(white)("XXX")rArr (x+1)(x-1)=0#

#rArr "Either "#
#color(white)("xxxxxxxx"){: ((x+1)=0," or ",(x-1)=0), (rarr x=-1,,rarr x=+1) :}#

Mar 9, 2018

Answer:

#x=1# or #x= -1#

Explanation:

#x^2-1=0#

#:.x^2=1#

#:.x=sqrt1#

#:.x=1# or#x=-1#