document.write( "Question 4399: You have a given set, of all polynomials of the form p(t) = a + t^2, where
\n" ); document.write( "a is in R (reals). How do you determine whether that given set is a subspace
\n" ); document.write( "of P(sub n) for an appropriate value of n?
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Algebra.Com's Answer #2012 by khwang(438)\"\" \"About 
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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)
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\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
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\n" ); document.write( "\n" ); document.write( " Kenny
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