document.write( "Question 18656: ABCD is a sqaure. The midpoints of BC and CD are M and N respectively.
\n" ); document.write( "a) Express vector AM and vector An as linear combinations of vector AB and vector AD.
\n" ); document.write( "b) Express vector AB and vector AD as linear combinations of vector AM and vector AN.
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Algebra.Com's Answer #9052 by venugopalramana(3286)\"\" \"About 
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ABCD is a sqaure. The midpoints of BC and CD are M and N respectively.
\n" ); document.write( "a) Express vector AM and vector An as linear combinations of vector AB and vector AD.
\n" ); document.write( "b) Express vector AB and vector AD as linear combinations of vector AM and vector AN.
\n" ); document.write( "ABCD being a square we have vector AB= vector DC
\n" ); document.write( "and vector AD=vector BC
\n" ); document.write( "but M is the mid point of BC .so vector BM=vector BC/2=vector AD/2
\n" ); document.write( "anfd N is the midpoint of CD.so vector NC=vector DC/2=vector AB/2
\n" ); document.write( "taking triangle ABM..we have vector AB+vector BM=vector AM
\n" ); document.write( " or...vector AM=vector AB+vector AD/2...............(1)
\n" ); document.write( "similarly we have from the polygon ABCN..
\n" ); document.write( "vector AB+vector BC+vector CN=vector AN
\n" ); document.write( "vector AN=vector AB+vector AD-vector NC=vector AB+vector AD-vector AB/2..or
\n" ); document.write( "vector AN=vector AB/2+vector AD..............(2)
\n" ); document.write( "from 2*(2)-(1) we get ..2*vector AN-vector AM=(2-1/2)(vector AD)=(3/2)vector AD
\n" ); document.write( "hence ...vector AD=(2/3)(2*vector AN-vector AM)..similarly by taking 2*(2)-(1),we can find AB in terms of AM and AN
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\n" ); document.write( " How do the graphs of y=X+3 (in
\n" ); document.write( "square root) compare the graph of y=x (insquare root) where x is greater
\n" ); document.write( "or equal to 0. And can you also graph y=f(x)+5
\n" ); document.write( "y=SQRT(x+3)...for every value of x we get 2 values for y ..one +ve and anpther -ve.further x cannot be less than -3 as it will lead to -ve number under square root which is imaginary.so the tabulation reads as follows.now you can plot the graph,i suppose.
\n" ); document.write( "x.....0.......1......2......3......-1......-2......-3
\n" ); document.write( "y.....3^0.5...2......5^0.5..6^0.5...2^0.5..1.......0
\n" ); document.write( "y....-3^0.5..-2.....-5^0.5.-6^0.5..-2^0.5.-1.......0
\n" ); document.write( "\"+graph%28+300%2C+300%2C+-3%2C+5%2C+-5%2C+5%2C+%2B%28x%2B3%29%5E0.5%2C-%28x%2B3%29%5E0.5%29+\"
\n" ); document.write( "y=sqrtx
\n" ); document.write( "x.....0.......1......2......3.......4
\n" ); document.write( "y.....0.......1......2^0.5..3^0.5...2
\n" ); document.write( "y.....0......-1.....-2^0.5.-3^0.5..-2\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+300%2C+300%2C+-3%2C+5%2C+-5%2C+5%2C+%2B%28x%29%5E0.5%2C-%28x%29%5E0.5%29+\"
\n" ); document.write( "graph y=f(x)+5...WHAT IS f(x)???????cant do wiyhout that\r
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