document.write( "Question 1158340: let f(x) = 3x^2 + 2x -1 and g(x) = 5x + 7 find (fog)(-2)\r
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Algebra.Com's Answer #781262 by ikleyn(52798) $\"\"$ $\"About$

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document.write( "The easiest way is to calculate g(-2) first\r\n" );
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document.write( "    g(-2) = 5*(-2) + 7 = -10 + 7 = -3.\r\n" );
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document.write( "and then substitute this value  g(-2) = -3 into the formula for f(x).\r\n" );
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document.write( "So,  (fog) (-2) = f(-3) = 3*(-3)^2 + 2*(-3) - 1  = 27 - 6 - 1 = 20  is your answer.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The meaning of this operation, (fog), which is called \"the composition of functions g and f\", is that\r
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