Find the angle to intersection of the following curves :

y = 4 –x2 and y = x2

Given:


Curves y = 4 – x2 ...(1)


& y = x2 ...(2)


Solving (1) & (2),we get


y = 4 – x2


x2 = 4 – x2


2x2 = 4


x2 = 2


x = ±


Substituting in y = x2 ,we get


y = ()2


y = 2


The point of intersection of two curves are (,2) & (, – 2)


First curve y = 4 – x2


Differentiating above w.r.t x,


= 0 – 2x


m1 = – 2x ...(3)


Second curve y = x2


Differentiating above w.r.t x,


= 2x


m2 = 2x ...(4)


At (,2),we have,


m1 = – 2x


– 2×


m1 = – 2


At (,2),we have,


m2 = – 2x


2 = 2


When m1 = – 2 & m2 = 2



tanθ


tanθ


tanθ


tanθ


θ = tan – 1()


θ38.94


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