问题标题：
帮我看一下这个哪里错了.1/2(t-4)(4t-16)+1/2[（4t-16)+(t-1)]×3-1/2(t-1)(t-1）=1/2×（4t^2-16t-16t+64)+1/2×(4t^2-4t-16t+16)×3-1/2×(t^2-2t+1)=2t^2-16t+32+1/2×（12t^2-60t+48)-1/2t^2+t-1/2=2t^2-16t+32+6t^2-30t+24-1/2t^2+t-1/2=15t^2-45t+
问题描述：
帮我看一下这个哪里错了.
1/2(t-4)(4t-16)+1/2[（4t-16)+(t-1)]×3-1/2(t-1)(t-1）
=1/2×（4t^2-16t-16t+64)+1/2×(4t^2-4t-16t+16)×3-1/2×(t^2-2t+1)
=2t^2-16t+32+1/2×（12t^2-60t+48)-1/2t^2+t-1/2
=2t^2-16t+32+6t^2-30t+24-1/2t^2+t-1/2
=15t^2-45t+111/2
黄国强回答：
1/2(t-4)(4t-16)+1/2[（4t-16)(t-1)]×3-1/2(t-1)(t-1）
=2(t-4)²+6(t-4)(t-1)-1/2(t-1)²
=2(t²-8t+16)+6(t²-5t+4)-1/2(t²-2t+1)
=2t²-16t+32+6t²-30t+24-t²/2+t-1/2
=15t²/2-45t+111/2
你就最后一步错了.其它都对
2t²+6t²-1/2t²=15/2t²
刘翔回答：
帮我算出结果。谢谢。
黄国强回答：
1/2(t-4)(4t-16)+1/2[（4t-16)+(t-1)]×3-1/2(t-1)(t-1）=1/2×（4t^2-16t-16t+64)+1/2×(4t^2-4t-16t+16)×3-1/2×(t^2-2t+1)=2t^2-16t+32+1/2×（12t^2-60t+48)-1/2t^2+t-1/2=2t^2-16t+32+6t^2-30t+24-1/2t^2+t-1/2=15t^2/2-45t+111/2请采纳，谢谢
刘翔回答：
结果不对。谢谢
黄国强回答：
那可能是你题目错了
刘翔回答：
1/2(t-4)(4t-16)+1/2[（4t-16)+(t-1)]×3-1/2(t-1)(t-1）题目没错。
黄国强回答：
你确定[（4t-16)+(t-1)]是加，而不是乘吗？你原来做的是乘
刘翔回答：
就是加你用乘法分配律再做一遍
黄国强回答：
1/2(t-4)(4t-16)+1/2[（4t-16)+(t-1)]×3-1/2(t-1)(t-1）=2(t-4)²+6(t-4)+3(t-1)/2-1/2(t-1)²=2(t²-8t+16)+6t-24-3t/2+3/2-1/2(t²-2t+1)=2t²-16t+32+6t-24-3t/2+3/2-t²/2+t-1/2=3t²/2-21t/2+9
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