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If x>2,then x2-x-6/x2-4=

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(x^2-x-6)/(x^2-4)=(*)\\------------\\x^2-x-6=0\\a=1;\ b=-1;\ c=-6\\\Delta=b^2-4ac;\ \Delta=(-1)^2-4\cdot1\cdot(-6)=1+24=25\\\\x_1=(-b-\sqrt\Delta)/(2a);\ x_2=(-b+\sqrt\Delta)/(2a)\\\\x_1=(1-√(25))/(2\cdot1)=(1-5)/(2)=(-4)/(2)=-2\\\\x_2=(1+√(25))/(2\cdot1)=(1+5)/(2)=(6)/(2)=3\\\\x^2-x-6=(x+2)(x-3)

---------------------\\x^2-4=x^2-2^2=(x-2)(x+2)\\-------------------\\\\(*)=((x+2)(x-3))/((x-2)(x+2))=(x-3)/(x-2)


User Anthony Forloney
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