document.write( "Question 30626: If f(x)=x^2-x and g(x)=-3+x find the following:
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document.write( "(a) f(g(x)) (b) g(f(x)) (c) f(f(-1)) (d) g(g(-3)) \n" );
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Algebra.Com's Answer #17360 by sdmmadam@yahoo.com(530)![]() ![]() ![]() You can put this solution on YOUR website! If f(x)=x^2-x and g(x)=-3+x find the following: \n" ); document.write( "(a) f(g(x)) (b) g(f(x)) (c) f(f(-1)) (d) g(g(-3))\r \n" ); document.write( "\n" ); document.write( "f(x)=x^2-x ----(1) \n" ); document.write( "g(x)=-3+x ----(2)\r \n" ); document.write( "\n" ); document.write( "(a) f(g(x)) = f(-3+x) using (2) \n" ); document.write( "= f(x-3) (using additive commutativity we have (-3+x)= (x-3) ) \n" ); document.write( "=f(t) where t = (x-3)----(*) \n" ); document.write( "= t^2-t using (1) \n" ); document.write( "= (x-3)^2-(x-3)using(*) \n" ); document.write( "=x^2-6x+9-x+3 \n" ); document.write( "=x^2-6x-x+9+3 \n" ); document.write( "=x^2-7x+12\r \n" ); document.write( "\n" ); document.write( "b)g(f(x)) = g(x^2-x) using (1) \n" ); document.write( "=g(u) where u = x^2-x ----(**) \n" ); document.write( "= -3+u using (2) \n" ); document.write( "= -3+ (x^2-x) using(**) \n" ); document.write( "= x^2-x-3\r \n" ); document.write( "\n" ); document.write( "c) f(f(-1)) \n" ); document.write( "= f[(-1)^2-(-1)] (using x = -1 in (1)which is f(x)=(x^2-x)) \n" ); document.write( "=f[1+1] \n" ); document.write( "=f(2) \n" ); document.write( "= [(2)^2-(2)] (using x = 2 in (1)which is f(x)=(x^2-x)) \n" ); document.write( "= 4-2 \n" ); document.write( "=2\r \n" ); document.write( "\n" ); document.write( "(d) g(g(-3)) \n" ); document.write( "= g[-3+(-3)] using x = -3 in (2) which is g(x) = -3+x ) \n" ); document.write( "=g(-3-3) \n" ); document.write( "=g(-6) \n" ); document.write( "=[-3+(-6)] using x = -6 in (2) which is g(x) = -3+x ) \n" ); document.write( "= (-3-6) \n" ); document.write( "= -9\r \n" ); document.write( "\n" ); document.write( "Answer: a)f(g(x)) = x^2-7x+12 \n" ); document.write( "b)g(f(x)) = x^2-x-3 \n" ); document.write( "c) f(f(-1))=2 \n" ); document.write( "(d) g(g(-3))= -9\r \n" ); document.write( "\n" ); document.write( " \r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |