Sunday

February 1, 2015

February 1, 2015

Posted by **Lori** on Saturday, November 21, 2009 at 11:51am.

a^4 – 5a^2 + 4 = 0

I am having problems figuring out what method to use to solve this problem. I need to show my steps and I am not sure how to do this. Can someone help? Thanks.

- College Math II -
**drwls**, Saturday, November 21, 2009 at 12:01pmThis equation can be solved by factoring. Have you learned how to do that yet? You should have.

This is not college level math. It is taught in the ninth grade

Hint: one of the factors is (a-4)

- College Math II (correction) -
**drwls**, Saturday, November 21, 2009 at 12:08pmOK, I made a mistake. Sorry about that. I didn't notice that is was fourth order.

The factors are:

(a^2-2)(a^2 +2)

which can be factored again to give

(a + sqrt2)(a - sqrt2)(a + isqrt2)(a - isqrt2)

Set that equal to zero and you will see that you have an answer whenever one of the factors is zero.

(i is the square root of -1)

**Answer this Question**

**Related Questions**

College Math II - Solve by any method. x(x + 1) = 12 I am not sure what method ...

Math - How do I solve these problems, I really need help. Solve by substitution ...

Substitution Method-Plz help - Use the Substitution method to solve the system ...

math,algebra II - I need someone to explain to me step by step the process of ...

Algebra - How do I solve by the substitution method? 7x +6y=13 x= 35-5y. I need ...

math - I'm having trouble trying to identify which method is best to use for ...

math - Solve by elimination method. 2r-5s=-33 5r+2s=48 Solve by substitution ...

math - Solve by elimination method. 2r-5s=-33 5r+2s=48 Solve by substitution ...

Math - Solve by eliminnation methods 2x-4y=5 2x-4y=6 solve the system by ...

math - Please solve the system with the elimination method. Explain each step as...