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Trigonometric identities
Pythagorean, double-angle and sum identities, verified by simplification.
Identities are equations true for every angle. The Pythagorean identity sin²x + cos²x = 1 is Pythagoras on the unit circle; the double-angle and sum formulas follow from it and rotation. To verify one, simplify the difference of the two sides to zero.
ਕੰਮ ਉਦਾਹਰਨ · simplify sin(x)^2 + cos(x)^2
Simplify sin(x)^2 + cos(x)^2
ਕਦਮ ਦਰ ਕਦਮ
- \sin^{2}{\left(x \right)} + \cos^{2}{\left(x \right)}
Start from the expression.
- 1
Simplify.
ਜਵਾਬ ਦਿਓ
ਹੁਣ ਤੁਸੀਂ ਇੱਕ ਸਮੱਸਿਆ ਚੁਣੋ, ਜਾਂ ਆਪਣਾ ਆਪ ਲਿਖੋ ਜਾਂ ਖਿੱਚੋ। ਹਰ ਕਦਮ, ਇੱਕ ਤਸਵੀਰ, ਜਵਾਬ ਜਦੋਂ ਤੱਕ ਤੁਸੀਂ ਪੁੱਛਦੇ ਹੋ, ਲੁਕਿਆ ਰਹਿੰਦਾ ਹੈ।
ਇੱਥੇ ਵਰਤੇ ਨਿਸ਼ਾਨ
ਕਿਸੇ ਵੀ ਨਿਸ਼ਾਨ ਨੂੰ ਦਬਾਉ, ਜਿਸ ਵਿੱਚ ਪੂਰੀ ਪਰਿਭਾਸ਼ਾ, ਇੱਕ ਤਸਵੀਰ ਅਤੇ ਹਰ ਅੱਖਰ ਦਾ ਅਰਥ ਹੈ ।
ਕਿਵੇਂ: Trigonometric identities
- Start from the expression.
- Simplify.
ਲੋਕ ਪੁੱਛਦੇ ਹਨ
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.
ਹੋਰ ਵਿੱਚ Trigonometry
The unit circleTrigonometric equationsDegrees and radiansRight-triangle trigonometry (SOH-CAH-TOA)Law of sines and law of cosinesGraphs of sine, cosine and tangentInverse trigonometric functions