Nine isosceles triangles whose angles give a fixed integer both with sine and cosine.

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$a+b>c,a+c>b,b+c>a$

I have a maximum of nine triangles whose perimeters equal $11,12,13,14,15,16,17,18,19$

side of triangle are $5$ and $5$ and base $1$

side of triangle are $5$ and $5$ and base $2$

side of triangle are $5$ and $5$ and base $3$

side of triangle are $5$ and $5$ and base $4$

side of triangle are $5$ and $5$ and base $5$

side of triangle are $5$ and $5$ and base $6$

side of triangle are $5$ and $5$ and base $7$

side of triangle are $5$ and $5$ and base $8$

side of triangle are $5$ and $5$ and base $9$

$ \cos^2A+\cos^2B+\cos^2C+\sin^2A+\sin^2B+\sin^2C=3$

For:the side of 5,5 and 1 the angles are

$0.1^2+0.1^2+0.98^2+\sqrt0.99^2+\sqrt0.99^2+\sqrt(1-0.98^2)^2=3$

and sides of 5,5 and 4

$0.4^2+0.4^2+0.68^2+\sqrt0.84^2+\sqrt0.84^2+\sqrt(1-0.68^2)^2=3$

Question : Does finding the sine of all three angles, which are fixed integers would be easier to construct $pi$ using Taylor's series for $\arcsin$? The sum of 3 $\arcsin\theta$ are $pi$