若多项式a²-a+2的值为7,则多项式-1/5a²+1/5a-3的值为____________.
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![若多项式a²-a+2的值为7,则多项式-1/5a²+1/5a-3的值为____________.](/uploads/image/z/5296824-0-4.jpg?t=%E8%8B%A5%E5%A4%9A%E9%A1%B9%E5%BC%8Fa%26%23178%3B-a%2B2%E7%9A%84%E5%80%BC%E4%B8%BA7%2C%E5%88%99%E5%A4%9A%E9%A1%B9%E5%BC%8F-1%2F5a%26%23178%3B%2B1%2F5a-3%E7%9A%84%E5%80%BC%E4%B8%BA____________.)
若多项式a²-a+2的值为7,则多项式-1/5a²+1/5a-3的值为____________.
若多项式a²-a+2的值为7,则多项式-1/5a²+1/5a-3的值为____________.
若多项式a²-a+2的值为7,则多项式-1/5a²+1/5a-3的值为____________.
a²-a+2的值为7
∴a²-a=5
-1/5a²+1/5a-3
=-1/5(a²-a)-3
=-1/5×5-3
=-4