Find a basis and dimension of a vector space

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To find the basis and dimension of the vector spaces V and W, one must first interpret the definitions accurately. V is defined by conditions involving the polynomial's values and its derivative at specific points, while W is characterized by polynomials that vanish at x=1. The discussion highlights that W can be expressed as W = (X-1)R3[X], indicating it is isomorphic to R3[X], which implies a dimension of 3 for W. The conditions for V require further clarification, particularly regarding the derivative at x=0, which is crucial for determining its basis and dimension. Understanding these relationships and conditions is essential for solving the problem effectively.
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Homework Statement


Find basis and dimension of V,W,V\cap W,V+W where V=\{p\in\mathbb{R_4}(x):p^{'}(0) \wedge p(1)=p(0)=p(-1)\},W=\{p\in\mathbb{R_4}(x):p(1)=0\}

Homework Equations


-Vector spaces

The Attempt at a Solution


Could someone give a hint how to get general representation of a vector in V and W?
 
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Look in your course notes when it talks about "general representation of a vector".
You have definitions of the vector spaces - so start with what the symbols turn into in English.
 
I'm not sure what the operator ^ means in the definition of ##V## so I can't help.
For ##W##, you can notice that ##W = (X-1) \mathbb{R}_3[X] ## is isomorphic to ##\mathbb{R}_3[X]##, so what can you say about the dimension of 2 isomorphic vector spaces ? Secondly, a vector space isomorphism sends a base to a base.
 
The only thing I have a question about is "p'(0)^p(1)= p(0)= p(-1)". The "^" typically means "and" so one condition is that p(1)= p(0)= p(-1) but the "p'(0)" is incomplete- nothing is said about the derivative at 0. What must be true about it? p in R^4 is of the form ax^4+ bx^3+ cx^2+ dx+ e and "p(1)= p(0)= p(-1)" requires that a+ b+ c+ d+ e= e= a- b+ c- d+ e. But, again, what is required of "p'(0)= d"?
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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