no of solution of the equation x plus 2 tanx = pie/2 in the interval of 0 to 2 pie
Answer: 3
Step-by-step solution
Step 1: Rearrange into two intersecting functions
We can rewrite the given equation x+2tanx=2π by isolating the trigonometric function tanx. Subtracting x from both sides and dividing by 2 gives tanx=21(2π−x)=4π−2x. Thus, the solutions correspond to the points of intersection between the curve y=tanx and the line y=4π−2x on the interval [0,2π].
Step 2: Analyze the functions on the sub-intervals
The tangent function tanx has vertical asymptotes at x=2π and x=23π. Therefore, the domain [0,2π] splits naturally into three continuous intervals: [0,2π), (2π,23π), and (23π,2π]. On each interval, y1=tanx is strictly increasing, while the line y2=4π−2x is strictly decreasing.
Step 3: Check intersections in each interval
In [0,2π), y1 increases from 0 to ∞ while y2 decreases from 4π≈0.785 to 0, yielding exactly 1 root. In (2π,23π), y1 increases continuously from −∞ to ∞, so it intersects the line exactly once. In (23π,2π], y1 increases from −∞ to 0 while y2 takes values in [−43π,−2π)≈[−2.36,−1.57]; since y1(2π)=0>y2(2π)=−43π, the Intermediate Value Theorem ensures exactly 1 intersection here as well.
Step 4: Sum the total number of solutions
Since there is exactly 1 solution in each of the 3 disjoint sub-intervals, the equation x+2tanx=2π has a total of 3 solutions in the interval [0,2π].