Question

Stiind ca x^8=5,calculati A)(x+1)(x-1)(x^2+1)(x^4+1) B)(3x-2)(3x+2)(9x^2+4)(81x^4+16)

Answer 1

a) =(x²-1)(x⁶+x²+x⁴+1)
=x⁸+x⁴+x⁶+x²-x⁶-x²-x⁴-1
=x⁸-1=5-1=4

b) =(9x²-4)(729x⁶+144x²+324x⁴+64)
=6561x⁸+1296x⁴+2916x⁶+576x²-2916x⁶-576x²-1296x⁴-256
=6561x⁸-256=6561·5-256=32805-256=32549