數學難題?大家快點來幫我解題

1.因式分解4(x＋1)(x＋3)(x＋5)(x＋7)＋64
Sol
(x+1)(x+3)(x+5)(x+7)+16
=(x+1)(x+7)(x+3)(x+5)+16
=(x^2+8x+7)(x^2+8x+15)+16
=(x^2+8x)^2+22(x^2+8x)+105+16
=(x^2+8x)^2+22(x^2+8x)+121
=(x^2+8x+11)^2
4(x＋1)(x＋3)(x＋5)(x＋7)＋64=4(x^2+8x+11)^2

2. (√26+√8)/(√234+√72－√286－√88)
= (√13+√4)/(√117+√36－√143－√44)
= (√13+2)/(3√13+6－√11*√13－2√11)
= (√13+2)/(3√13－√11*√13+6－2√11)
= (√13+2)/[(√13(3－√11)+2(3－√11))
= 1/(3－√11)
= (3+√11)/(9－11)
=－(3+√11)/2

1.
原式
=4(x+1)(x+7)(x+3)(x+5)+64
=4(x^2+8x+7)(x^2+8x+15)+64
=4(x^2+8x)^2+88(x^2+8x)+484
=4[(x^2+8x)+11)^2
=4(x^2+8x+11)^2

2012-11-23 21:41:32 補充：
2.樓上已答不贅述