Nilaikan
-\frac{\sqrt{2}}{2}\approx -0.707106781
Kongsi
Disalin ke papan klip
\cos(90+45)=\cos(90)\cos(45)-\sin(45)\sin(90)
Gunakan \cos(x+y)=\cos(x)\cos(y)-\sin(y)\sin(x) dimana x=90 dan y=45 untuk mendapatkan hasil.
0\cos(45)-\sin(45)\sin(90)
Dapatkan nilai \cos(90) daripada nilai trigonometric.
0\times \frac{\sqrt{2}}{2}-\sin(45)\sin(90)
Dapatkan nilai \cos(45) daripada nilai trigonometric.
0\times \frac{\sqrt{2}}{2}-\frac{\sqrt{2}}{2}\sin(90)
Dapatkan nilai \sin(45) daripada nilai trigonometric.
0\times \frac{\sqrt{2}}{2}-\frac{\sqrt{2}}{2}\times 1
Dapatkan nilai \sin(90) daripada nilai trigonometric.
-\frac{\sqrt{2}}{2}
Lakukan pengiraan.
Contoh
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometri
4 \sin \theta \cos \theta = 2 \sin \theta
Persamaan linear
y = 3x + 4
Aritmetik
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Matriks
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Persamaan serentak
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Pembezaan
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Pengamiran
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Had
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}