Question

(к+1)^2 (2 (к+1)^2-1) решите плз

Answer 1

(k+1)²(2(k+1)²-1)=(k+1)²(2(k²+2k+1)-1)=(k+1)²(2k²+4k+2-1)=(k+1)²(2k²+4k+1)=(k+1)²·2k²+(k+1)²·4k+(k+1)²=(k²+2k+1)·2k²+(k²+2k+1)·4k+k²+2k+1=2k⁴+4k³+2k²+4k³+8k²+4k+k²+2k+1=2k⁴+8k³+11k²+6k+1.