4 sin2x = 1.
Then,
(2sinx)2 = 1,
2sinx = ±1, and
sinx = ±½.
Whence,
x = 90° or 270°;
or, in radians,
x = π/2 or 3π/2.
2 sin2 x + sin x = 1. Letting s = sin x, we have: 2s2 + s - 1 = (2s - 1)(s + 1) = 0; whence, sin x = ½ or -1, and x = 30° or 150° or 270°. Or, if you prefer, x = π/6 or 5π/6 or 3π/2.
No, (sinx)^2 + (cosx)^2=1 is though
That factors to (a + 1)(a + b) a = -1, -b b = -a
You have to put your heart into it!
The answer is 1. sin^2 x cos^2/sin^2 x 1/cos^2 cos^2 will be cancelled =1 sin^2 also will be cancelled=1 1/1 = 1
2 sin^2 theta = 1/4 sin^2 theta = 1/8 sin theta = sqrt(1/8) theta = arcsin(sqrt(1/8))
22
If x = sin θ and y = cos θ then: sin² θ + cos² θ = 1 → x² + y² = 1 → x² = 1 - y²
2 x cosine squared x -1 which also equals cos (2x)
2 sin2 x + sin x = 1. Letting s = sin x, we have: 2s2 + s - 1 = (2s - 1)(s + 1) = 0; whence, sin x = ½ or -1, and x = 30° or 150° or 270°. Or, if you prefer, x = π/6 or 5π/6 or 3π/2.
Multiply both sides by sin(1-cos) and you lose the denominators and get (sin squared) minus 1+cos times 1-cos. Then multiply out (i.e. expand) 1+cos times 1-cos, which will of course give the difference of two squares: 1 - (cos squared). (because the cross terms cancel out.) (This is diff of 2 squares because 1 is the square of 1.) And so you get (sin squared) - (1 - (cos squared)) = (sin squared) + (cos squared) - 1. Then from basic trig we know that (sin squared) + (cos squared) = 1, so this is 0.
X=1
sin(x)*sin2(x) = 1 so sin3(x) = 1 so that sin(x) = cuberoot(1) = 1 then x = pi/2 + n*pi where n is an integer.
No, (sinx)^2 + (cosx)^2=1 is though
That factors to (a + 1)(a + b) a = -1, -b b = -a
There is a hint to how to solve this in what is required to be shown: a and b are both squared.Ifa cos θ + b sin θ = 8a sin θ - b cos θ = 5then square both sides of each to get:a² cos² θ + 2ab cos θ sin θ + b² sin² θ = 64a² sin² θ - 2ab sin θ cos θ + b² cos² θ = 25Now add the two together:a² cos² θ + a² sin² θ + b² sin² θ + b² cos² θ = 89→ a²(cos² θ + sin² θ) + b² (sin² θ + cos² θ) = 89using cos² θ + sin² θ = 1→ a² + b² = 89
2 sin2(x) + sin(x) - 1 = 0(2 sin + 1) (sin - 1) = 0Either 2 sin(x) + 1 = 02sin(x) = -1sin(x) = -0.5x = 210°, 330°or sin(x) - 1 = 0sin(x) = 1x = 90°