已知aB满足sina=根号5

已知实数a满足|2011-a| 根号a-2012=a,求a-2011的平方的值

已知实数a满足|2011-a| 根号a-2012=a,求a-2011的平方的值设A = (a - 2011)则 |2011-a| √(a-2012) = a |A| √(A - 1) = A 2011情况1: A ＞0时，√(A - 1) = 2011 ===> (A - 1) = 2011² ===> A = 2011² 1情况1: A ＜0时，√(A - 1) = 2A 2011 ① ===> (A - 1) = 4A² 4*2011A 2011² 。 ===> 4A² (4*2011 1)A (2011² 1) ===> △ = (4*...全部

  已知实数a满足|2011-a| 根号a-2012=a,求a-2011的平方的值设A = (a - 2011)则 |2011-a| √(a-2012) = a |A| √(A - 1) = A 2011情况1: A ＞0时，√(A - 1) = 2011 ===> (A - 1) = 2011² ===> A = 2011² 1情况1: A ＜0时，√(A - 1) = 2A 2011 ① ===> (A - 1) = 4A² 4*2011A 2011² 。
   ===> 4A² (4*2011 1)A (2011² 1) ===> △ = (4*2011 1)² - 16*(2011² 1) = (4*2011 1)² - (4*2011² 16) = - 17*15 ＜0 ①无解a-2011的平方的值: (2011² 1)²。
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