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Graphs of sine, cosine and tangent

Amplitude, period, phase shift and the shape of periodic motion.

y = A sin(Bx + C) + D has amplitude |A|, period 2π/B, phase shift −C/B and midline D. Picture it: the graph is a wave; changing each parameter stretches, squeezes or slides it. Think it: every periodic signal (sound, light, tides) is a sum of such waves (Fourier), so these four parameters describe all of them.

Ýüklenen mysal · y = sin(x) + cos(2x)

Algebra · Functions

Graph and analyse sin(x) + cos(2x)

y = \sin{\left(x \right)} + \cos{\left(2 x \right)}

Adım adım

  1. \sin{\left(x \right)} + \cos{\left(2 x \right)}

    An expression in x. Here is what it does.

  2. x = - \frac{5 \pi}{6}, x = - \frac{\pi}{6}, x = \frac{\pi}{2}

    Real zeros (where the graph crosses the axis).

  3. \frac{d}{dx} = - 2 \sin{\left(2 x \right)} + \cos{\left(x \right)}

    Derivative (slope).

Jawaby görkez
\sin{\left(x \right)} + \cos{\left(2 x \right)}

Indi sen Bir meseläni saýla, ýa-da ýaz ýa-da özüňi surata çek. Her ädim, bir resim, jogap sorag berlençä gizlenýär.

Özüň işle

Mugt hasap her bir ders üçin notlar goşýar, tamamlanan zadyňyzyň ýazgysyny, çözen problemaňyzy bir ýerde, we bu sahypa barada sorap biljek mugallymy. Matematika özüçe her kim üçin açyk, girseň ýa girmeseň.

_Gün _Giriş

Şu ýerde ulanylan simwollar

Eň täze düşündirme, surat, we her harpyň manysy üçin her bir simwoly basyň.

Nädip: Graphs of sine, cosine and tangent

  1. An expression in x. Here is what it does.
  2. Real zeros (where the graph crosses the axis).
  3. Derivative (slope).

Adamlar soraýan soraglar

Why radians instead of degrees?

A radian is the angle whose arc equals the radius, so it is a pure ratio rather than an arbitrary 1/360 of a turn. With radians the derivative of sin x is exactly cos x; with degrees a factor of π/180 appears everywhere.

Why does sin x = 1/2 have infinitely many solutions?

Sine repeats every full turn, and within one turn it reaches 1/2 twice (at π/6 and 5π/6). Add any whole number of turns to either and it is still true.

How do I remember the exact values?

Two triangles: the 45-45-90 with sides 1, 1, √2 and the 30-60-90 with sides 1, √3, 2. Every value for 30°, 45° and 60° is a ratio of those sides; symmetry gives the rest of the circle.

_Ýaşa Trigonometry

The unit circleTrigonometric equationsTrigonometric identitiesDegrees and radiansRight-triangle trigonometry (SOH-CAH-TOA)Law of sines and law of cosinesInverse trigonometric functions