where [tex]n[/tex] is any integer. If we take [tex]n=\pm1[/tex] we should get the two solutions immediately adjacent to the one near [tex]x=0[/tex] that still lie in the interval [tex]-5\le x\le5[/tex]. So the other two zeros are [tex]x=-\arcsin\dfrac1{50}\pm\pi[/tex].
The tangent line to the curve at any [tex]x[/tex] is determined by the value of the derivative of the function at that value of [tex]x[/tex]. So first compute the derivative: