Question

Докажите тождество пож (б)

Answer 1

a)=> (a²-4b²)(a²+4b²)= a^{4}-16b^{4}

b)=>(x²-1)(x²+1)=> (x^{4}-1)(x^{4}+1) => x^{8}-1

c)=> (a^{3}-8)(a^{3}+8)=>a^{6}-64

d)=> c^{4}+c^{3}-2c^{2}-c^{3}-c^{2}+2c-2c^{2}-2c+4=>c^{4} -5c^{2}+4

Answer 2

б)

$\underbrace {(x-1)(x+1)}_{x^2-1}(x^2+1)(x^4+1)=\\\\=\underbrace {(x^2-1)(x^2+1)}_{x^4-1}(x^4+1)=\\\\=(x^4-1)(x^4+1)=x^8-1$