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Factorise 8y^3 - 15x^3

User Jeet Patel
by
4.4k points

1 Answer

3 votes

Answer:

(2y-cubert(15)x)(4y^2+2cubert(15)xy+cubert(15^2)x^2)

Explanation:

It almost look like someone possibly meant to write a perfect cube there instead of 51... but we can still factorize this... it just won't be as pretty.

The formula for factoring a difference of cubes is

u^3-v^3

=(u-v)(u^2+uv+v^2).

So the answer here is

(2y)^3-(cubert(15)x)^3

=(2y-cubert(15)x)(4y^2+2cubert(15)xy+cubert(15^2)x^2)

cubert means cube root of

The thing I'm cube rooting is the thing in ( ) next to the cubert.

Make sure you actually write the symbol for cube root instead of my notation.

User Pymkin
by
4.5k points