已知2a-b=3,求代数式3(a²+3/2a-2b+1)-1/2(6a²-3a-6b-2)的值
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![已知2a-b=3,求代数式3(a²+3/2a-2b+1)-1/2(6a²-3a-6b-2)的值](/uploads/image/z/765248-32-8.jpg?t=%E5%B7%B2%E7%9F%A52a-b%3D3%2C%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F3%28a%26%23178%3B%2B3%2F2a-2b%2B1%29-1%2F2%286a%26%23178%3B-3a-6b-2%29%E7%9A%84%E5%80%BC)
已知2a-b=3,求代数式3(a²+3/2a-2b+1)-1/2(6a²-3a-6b-2)的值
已知2a-b=3,求代数式3(a²+3/2a-2b+1)-1/2(6a²-3a-6b-2)的值
已知2a-b=3,求代数式3(a²+3/2a-2b+1)-1/2(6a²-3a-6b-2)的值
解
3(a²+3/2a-2b+1)-1/2(6a²-3a-6b-2)
=(3a²-3a²)+(9/2a+3/2a)+(-6b+3b)+(3+1)
=6a-3b+4
=3(2a-b)+4
=3×3+4
=13
3/2a是3/(2a)还是(3/2)*a?