Identify Conjugate of Denominator: Identify the conjugate of the denominator −3+2.The conjugate of a number of the form a+b is a−b. Therefore, the conjugate of −3+2 is −3−2.
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 will eliminate the square root in the denominator. This form of 1 is the conjugate of the denominator over itself.So, we multiply −3+27 by −3−2−3−2.
Apply Distributive Property: Apply the distributive property to the numerator.Multiply 7 by each term in the conjugate −3−2.7×(−3)=−217×(−2)=−72So, the numerator becomes −21−72.
Apply Difference of Squares: Apply the difference of squares formula to the denominator.The product of a binomial and its conjugate is the difference of squares:(−3+2)∗(−3−2)=(−3)2−(2)29−2=7So, the denominator becomes 7.
Combine Numerator and Denominator: Combine the simplified numerator and denominator. The fraction is now (−21−72)/7.
Simplify Fraction: Simplify the fraction by dividing each term in the numerator by the denominator.−721=−3−772=−2So, the simplified expression is −3−2.
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