If θ is the angle between the lines joining the points (0, 0) and B(2, 3), and the points C(2, -2) and D(3, 5), show that .

The given points are A(0,0),B(2,3) and C(2,-2),D(3,5).


The slope of line AB is


And the slope of line CD is


We know that angle between two lines with their slopes as m1 and m2 is given by







Hence proved.


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