Question 1038688
1. x^8+y^8
Not factorable with integers.
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 2. x^5-32y^5
= x^5 - (2y)^5
= (x - 2y)*(x^4 + x^3*2y + x^2*(2y)^2 + x*(2y)^3 + (2y)^4)
= {{{(x-2y)*(x^4 + 2x^3y + 4x^2y^2 + 8xy^3 + 16y^4)}}}
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 3. a^21+128c^7
= (a^3)^7 + (2c)^7
= {{{(a^3 + 2c)*(a^6 - a^5*2c + a^4*(2c)^2 - a^3*(2c)^3 + a^2*(2c)^4 - a*(2c)^5 + 64c^6)}}}
 4. x^10+y^10
= (x^2)^5 + (y^2)^5
Similar to #3
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 5. m^11-n^11
Similar to #2
= (m-n)*(m^10 ..... n^10)
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