document.write( "Question 4399: You have a given set, of all polynomials of the form p(t) = a + t^2, where
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document.write( "a is in R (reals). How do you determine whether that given set is a subspace
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document.write( "of P(sub n) for an appropriate value of n? \n" );
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Algebra.Com's Answer #2012 by khwang(438)![]() ![]() ![]() You can put this solution on YOUR website! For a given vector space V, a subset W is a subspace of V if and only \n" ); document.write( " if av+bw is in W for all v, w in W and scalars a,b.(reals here) \n" ); document.write( " \n" ); document.write( " Now W = {a + t^2| a is real} = set of polynomials in R with \n" ); document.write( " deg <=2 and the coefficient of t^2 = 1, the coefficient of t = 0. \n" ); document.write( " Clearly, W is a subset of P2 = {a + bt + ct^2| a,b,c are reals} \n" ); document.write( " = set of polynomials in R of degree <=2.\r \n" ); document.write( "\n" ); document.write( " But, W is not a subspace of P2. \n" ); document.write( " Since t^2 is in W but t^2 + t^2 = 2t^2 is not in W. \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " Kenny \n" ); document.write( " |