version 1.1, 2007/01/22 21:48:55
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version 1.4, 2009/07/06 17:12:47
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<problem> |
<problem> |
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<script type="loncapa/perl"> |
<script type="loncapa/perl"> |
$a1 = random(-6,6,4); |
$a1 = &random(-6,6,4); |
$a2 = random(-6,6,4); |
$a2 = &random(-6,6,4); |
$n1 = random(3,11,2); |
$n1 = &random(3,11,2); |
$n2 = random(2,10,2); |
$n2 = &random(2,10,2); |
$function = "$a1*cos($n1*x)+$a2*sin($n2*x)"; |
$function = "$a1*cos($n1*x)+$a2*sin($n2*x)"; |
$example=&xmlparse('An example would be <m eval="on">$(sin($n1\cdot x)+cos($n2\cdot x))/\sqrt{2}$</m>');</script> |
$example=&xmlparse('An example would be <m eval="on">$ (sin($n1\cdot x)+cos($n2\cdot x))/\sqrt{2} $</m>'); |
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</script> |
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<startouttext /> |
<startouttext /> |
Give an example of a function |
Give an example of a function |
<ol> |
<ol> |
<li>which is orthogonal to <algebra>$function</algebra> with respect to the |
<li>which is orthogonal to <algebra>$function</algebra> with respect to the scalar product |
scalar product |
<m>\[<g \mid h> = \frac{1}{\pi} \int_{-\pi}^{\pi}dx g(x) \cdot h(x)\]</m> |
<m>\[<g \mid h> = |
</li> |
\frac{1}{\pi} \int_{-\pi}^{\pi}dx g(x) \cdot h(x)\]</m> |
<li>whose norm is 1.</li> |
</li> |
</ol> |
<li>whose norm is 1.</li> |
<endouttext /> |
</ol><endouttext /> |
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<mathresponse answerdisplay="$example" cas="maxima" args="$function"> |
<mathresponse answerdisplay="$example" cas="maxima" args="$function"> |
<answer>overlap:integrate((RESPONSE[1])*(LONCAPALIST[1]),x,-%pi,%pi)/%pi; |
<answer> |
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overlap:integrate((RESPONSE[1])*(LONCAPALIST[1]),x,-%pi,%pi)/%pi; |
norm:integrate((RESPONSE[1])*(RESPONSE[1]),x,-%pi,%pi)/%pi; |
norm:integrate((RESPONSE[1])*(RESPONSE[1]),x,-%pi,%pi)/%pi; |
is(overlap=0 and norm=1);</answer> |
is(overlap=0 and norm=1); |
<textline readonly="no" size="50" /> |
</answer> |
<hintgroup showoncorrect="no"> |
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<mathhint name="ortho" args="$function" cas="maxima"> |
<textline readonly="no" size="50" /> |
<answer>overlap: integrate((LONCAPALIST[1])*(RESPONSE[1]),x,-%pi,%pi)/%pi; |
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is(not overlap = 0);</answer> |
<hintgroup showoncorrect="no"> |
</mathhint> |
<mathhint name="ortho" args="$function" cas="maxima"> |
<mathhint name="norm" args="$function" cas="maxima"> |
<answer> |
<answer>norm: integrate((RESPONSE[1])*(RESPONSE[1]),x,-%pi,%pi)/%pi; |
overlap: integrate((LONCAPALIST[1])*(RESPONSE[1]),x,-%pi,%pi)/%pi; |
is(not norm = 1);</answer> |
is(not overlap = 0); |
</mathhint> <hintpart on="norm"> |
</answer> |
<startouttext /> |
</mathhint> |
The function you have provided does not have a norm of one.<endouttext /> |
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</hintpart> |
<mathhint name="norm" args="$function" cas="maxima"> |
<hintpart on="ortho"> |
<answer> |
<startouttext /> |
norm: integrate((RESPONSE[1])*(RESPONSE[1]),x,-%pi,%pi)/%pi; |
The function you have provided is not orthogonal.<endouttext /> |
is(not norm = 1); |
</hintpart> |
</answer> |
</hintgroup> |
</mathhint> |
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<hintpart on="norm"> |
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<startouttext /> |
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The function you have provided does not have a norm of one. |
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<endouttext /> |
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</hintpart> |
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<hintpart on="ortho"> |
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<startouttext /> |
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The function you have provided is not orthogonal. |
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<endouttext /> |
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</hintpart> |
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</hintgroup> |
</mathresponse> |
</mathresponse> |
<postanswerdate><startouttext /><p>Note that with respect to the above norm, <m>$\cos(nx)$</m> is perpendicular to <m>$\sin(nx)$</m> and perpendicular to <m>$\cos(mx)$</m> for <m>$n\ne m$</m>.</p><endouttext /> |
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<postanswerdate> |
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<startouttext /> |
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<p> |
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Note that with respect to the above norm, <m>$ \cos(nx) $</m> is perpendicular to <m>$ \sin(nx) $</m> and perpendicular to <m>$ \cos(mx) $</m> for <m>$ n\ne m $</m>. |
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</p> |
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<endouttext /> |
</postanswerdate> |
</postanswerdate> |
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</problem> |
</problem> |