document.write( "Question 127643: 3. Show that the composition of two linear functions is also a linear function. \n" ); document.write( "
Algebra.Com's Answer #93525 by jim_thompson5910(35256)\"\" \"About 
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Let \r
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\n" ); document.write( "\n" ); document.write( "So \"%28f+o+g%29%28x%29=f%28g%28x%29%29=m%5B1%5D%28m%5B2%5Dx%2Bb%5B2%5D%29%2Bb%5B1%5D\"\r
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\n" ); document.write( "\n" ); document.write( "\"m%5B1%5Dm%5B2%5Dx%2Bm%5B1%5Db%5B2%5D%2Bb%5B1%5D\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "Since , this means that and . So this shows us that if f(x) and g(x) are linear, then (f o g)(x) is a linear function.\r
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\n" ); document.write( "\n" ); document.write( "Now let's verify this statement the other way. \r
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\n" ); document.write( "\n" ); document.write( "\"%28g+o+f%29%28x%29=g%28f%28x%29%29=m%5B2%5D%28m%5B1%5Dx%2Bb%5B1%5D%29%2Bb%5B2%5D\"\r
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\n" ); document.write( "\n" ); document.write( "Since , this means that and . So this shows us that if f(x) and g(x) are linear, then (g o f)(x) is a linear function.
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