I have a Problem with analytic of point
A(1/2,-3) and B(a,2a) are given if $AB^2$=3/4 find the sum of possible values of a
How can we square B ? Is $AB^2$ a line or something?
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you have $$\vec{AB}=\left[a-\frac{1}{2};2a+3\right]$$ so we get $$(\vec{AB})^2=\left(a-\frac{1}{2}\right)^2+(2a+3)^2=\frac{3}{4}$$ this is the dot product and must be solved for $a$ $$\vec{AB}=[x_B-x_A;y_B-y_A]$$
Dr. Sonnhard Graubner
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I am new to analytic geometry can you explain how you get AB? – Feb 12 '18 at 08:55
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can you proceed now? – Dr. Sonnhard Graubner Feb 12 '18 at 08:57
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Can you please write the formula of dot product too? – Feb 12 '18 at 09:36
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see here https://en.wikipedia.org/wiki/Dot_product – Dr. Sonnhard Graubner Feb 12 '18 at 10:43