positive a^3+b^3=(a+b)(a^2-ab+b^2) negative a^3-b^3=(a-b)(a^2+ab+b^2) 4.) x^3+1000=0 (factor the cubic) (5 and 6 factor the polynomial) 5.) 8x^3+64=0 6.)216x^3+27=0
@adrianluvvsyouu2
Whats the question?
4-6
theyre numbered its factoring polynomials
The fourth one is basically the formula I used earlier a^3 - b^3 = (a-b)(a^2 - ab + b^2) a^3 + b^3 = (a+b)(a^2 - ab + b^2) <-- Try using this one Basically you need to change 1000 into a number to the third power, said number is b, and x is a.
Same thing with the other two, change the values into a number to the third power (cubed) So 8 is the same as 2^3.. 64 is the same as 4^3.. this way you can plug them into this formula every single time without fail
im confused
how do i write it
You want it in either of these forms (a+b)(a^2 - ab + b^2) or (a-b)(a^2 - ab + b^2), depending on original expression.. if the two terms have a plus in between them, you use the formula that has (a+b), if the two terms have a minus between them you use the formula that has (a-b) Let me use an example with the first problem.. We have x^3 + 1000 The first thing I want to do is get it into the form a^3 + b^3, so that the formula works Basically, I already have x^3, now I just need to change 1000 into a number to the third power. 1000 is the same as 10^3, so I want to rewrite this as x^3 + 10^3, now it's in the same form as a^3 + b^3 where x = a and 10 = b Then I can plug this into the larger formula (a+b)(a^2 - ab + b^2) notice how I used the formula with the (a+b)? This is because the original expression had a plus between the two terms So now I can say, for every a in that formula, I just need to put an x For every b in that formula, I just need to put a 10... (x + 10)(x^2 - x * 10 + 10^2) Simplified to (x+10)(x^2 - 10x + 100)
thank you can u help me with the other 2
its not even a quiz its ok. ill find someone else.
Hey! I'm learning this in Algebra 2 right now, I can definitely help you. :3
thank youuuu
I can help you with 5 and 6 first, I'm much more familiar with these.
#5: Your equation is \[8x^3+64=0\], and you must use the formula to find the sum of cubes (since you are adding.) and the formula is: \[a^3 + b^3 = (a+b)(a^2 − ab + b^2 )\]
So first we take out the GCF (Greatest Common Factor), what's the biggest number that can go into both 8 and 64? (You tell me. :p)
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