What is the factors for #4x^2 -9#?

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Answer 1 · 2015-05-06T04:46:47

#4x^2 - 9 = (2x)^2 - 3^2#

We know that #color(blue)(a^2 - b^2 = (a+b)(a-b)#

Hence #(2x)^2 - 3^2 = (2x + 3)(2x - 3)#

The factors of #4x^2 - 9# are #color(green)((2x + 3)# and #color(green)((2x - 3)#

Answer 2 · 2015-05-06T04:47:17

The answer is #(4x^2-9)=(2x-3)(2x+3)#.

This is an example of the difference of squares, where #(a^2-b^2)=(a-b)(a+b)#.

#(4x^2-9)=((2x)^2-3^2)#

#a=2x#
#b=3#

#(4x^2-9)=(2x-3)(2x+3)#