Упростите выражение:1)(x+1)(x-1)-(x+5)(x-5)+(x+1)(x-5)...

Question

Упростите выражение:1)(x+1)(x-1)-(x+5)(x-5)+(x+1)(x-5) 2)81a^8-(3a^2-b-^3)(9a^4+b^6)(3a^2+b^3)

Answer 1

(x+1)(x-1)-(x+5)(x-5)+(x+1)(x-5)=x^2-1-x^2+25+x^2-5x+x-5=x^2-4x+19
81a^8-(3a^2-b^3)(9a^4+b^6)(3a^2+b^3)==81a^8-(9a^4-b^6)(9a^4+b^6)=81a^8-81a^8+b^12=b^12