Q. Simplify. Rationalize the denominator. −9+210
Identify Conjugate of Denominator: Identify the conjugate of the denominator −9+2.The conjugate of a number of the form a+b is a−b, and vice versa. Therefore, the conjugate of −9+2 is −9−2.
Multiply by Conjugate: Multiply the numerator and the denominator by the conjugate of the denominator.To rationalize the denominator, we multiply the fraction by a form of 1 that consists of the conjugate of the denominator over itself.−9+210 * −9−2−9−2
Distribute Multiplication in Numerator: Distribute the multiplication in the numerator.Multiply 10 by each term in the conjugate −9−2.10×(−9)=−9010×(−2)=−102So the numerator becomes −90−102.
Apply Difference of Squares: Apply the difference of squares in the denominator.When we multiply the conjugate pair, we get (−9+2)×(−9−2), which is a difference of squares.(−9)2−(2)2= 81 - 2= 79
Write Simplified Expression: Write the simplified expression.Now we have the numerator as −90−102 and the denominator as 79.So the simplified expression is 79−90−102.
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