How do you solve #2x^4 - 10x^2 = 0#?

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Answer 1 · 2015-10-31T16:04:53

# x = +sqrt 5 #
# x = - sqrt 5 #

Here,

It is easy to solve for quadratic function but difficult if the power rises up to more than 3,

in this case you let #x^2 = a#
Now replace the value of #x^2# with #a#

The new equation is,

#2a^2 - 10a# =0

Take 2 common for both the terms,

2 ( #a^2 - 5a #) =0

#a^2 - 5a = 0 #

#a^2 = 5a #

Cancel one a ,

SO,

#a = 5#

Now replace this value of a in #x^2#

SO,

#x^2# = 5
# x = +- sqrt 5 #

So, either, # x = +sqrt 5 #
or, # x = - sqrt 5 #