Solution 2.3:5c

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Current revision (11:13, 29 September 2008) (edit) (undo)
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If
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If <math>x=1</math> is a root of the equation, the equation should be satisfied if we substitute in <math>x=1</math> into it, i.e. <math>1^{2}+4\cdot 1+b=5+b</math> should be equal to zero, and this gives directly that <math>b=-5\,</math>.
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<math>x=\text{1 }</math>
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is a root of the equation, the equation should be satisfied if we substitute in
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<math>x=\text{1 }</math>
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into it,
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i.e.
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<math>1^{2}+4\centerdot 1+b=5+b</math>
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should be equal to zero, and this gives directly that
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<math>b=-\text{5}</math>.
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Current revision

If \displaystyle x=1 is a root of the equation, the equation should be satisfied if we substitute in \displaystyle x=1 into it, i.e. \displaystyle 1^{2}+4\cdot 1+b=5+b should be equal to zero, and this gives directly that \displaystyle b=-5\,.