https://www.khanacademy.org/math/geometry-home/right-triangles-topic/intro-to-the-trig-ratios-geo/v/basic-trigonometry 2023-04-19T21:28:53.788177796Z Intro to the trigonometric ratios Sin, cos, and tan are trigonometric ratios that relate the angles and sides of right triangles. Sin is the ratio of the opposite side to the hypotenuse, cos is the ratio of the adjacent side to the hypotenuse, and tan is the ratio of the opposite side to the adjacent side. They are often written as sin(x), cos(x), and tan(x), where x is an angle in radians or degrees. Sal Khan video https://cdn.kastatic.org/googleusercontent/92f-z9P3xlQjRzRxw0jbZbOpAzwmjBTqS0jsZc35x2__HYRgkdQOu9L4be8LG41cffV9nRfKOwGzLFG8nw-Oi_en Intro to the trigonometric ratios Sin, cos, and tan are trigonometric ratios that relate the angles and sides of right triangles. Sin is the ratio of the opposite side to the hypotenuse, cos is the ratio of the adjacent side to the hypotenuse, and tan is the ratio of the opposite side to the adjacent side. They are often written as sin(x), cos(x), and tan(x), where x is an angle in radians or degrees. https://cdn.kastatic.org/ka-youtube-converted/Jsiy4TxgIME.mp4/Jsiy4TxgIME.mp4 557 Trigonometry https://www.khanacademy.org/math/geometry/hs-geo-trig/xff63fac4:hs-geo-trig-ratios-similarity/a/opposite-adjacent-hypotenuse 2022-09-10T02:03:40.164764806Z Hypotenuse, opposite, and adjacent In a right triangle, the hypotenuse is the longest side, an "opposite" side is the one across from a given angle, and an "adjacent" side is next to a given angle. article https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-trig-ratios-intro/v/basic-trigonometry-ii 2021-06-30T17:32:36Z Trigonometric ratios in right triangles Sal shows a few examples where he starts with the two legs of a right triangle and he finds the trig ratios of one of the acute angles. Sal Khan video https://cdn.kastatic.org/googleusercontent/cwpGy84NzSmhKdw05CgXGtrk00QP2OcirhTztXczYdrISg6awjAEHFhgQLuF8VUYPmXsM-LOJBMBVSmZ3yP555zf Trigonometric ratios in right triangles Sal shows a few examples where he starts with the two legs of a right triangle and he finds the trig ratios of one of the acute angles. https://cdn.kastatic.org/ka-youtube-converted/G-T_6hCdMQc.mp4/G-T_6hCdMQc.mp4 731 Trigonometry https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-trig-ratios-intro/a/finding-trig-ratios-in-right-triangles 2022-09-10T02:03:40.164764806Z Trigonometric ratios in right triangles Learn how to find the sine, cosine, and tangent of angles in right triangles. article https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-trig-ratios-intro/e/trigonometry_1 2026-04-01T11:24:50.133517701Z Trigonometric ratios in right triangles Given the side lengths of a right triangle, find the sine, cosine, or tangent of one of the acute angles. Tomer Gal exercise https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-solve-for-a-side/v/example-trig-to-solve-the-sides-and-angles-of-a-right-triangle 2021-06-30T17:32:38Z Solving for a side in right triangles with trigonometry Sal is given a right triangle with an acute angle of 65° and a leg of 5 units, and he uses trigonometry to find the two missing sides. Sal Khan video https://cdn.kastatic.org/googleusercontent/X0ECxxkRbmZu7H78vm4EbH8BRKYqPBGlzkuAdFqDsmG5d33yLEW3qY54S02C0-YF6OUMI-SPnXfHJYAyuzICHfCYJQ Solving for a side in right triangles with trigonometry Sal is given a right triangle with an acute angle of 65° and a leg of 5 units, and he uses trigonometry to find the two missing sides. https://cdn.kastatic.org/ka-youtube-converted/l5VbdqRjTXc.mp4/l5VbdqRjTXc.mp4 424 Trigonometry https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-solve-for-a-side/a/unknown-side-in-right-triangle-w-trig 2025-02-11T16:42:34.189704851Z Solving for a side in right triangles with trigonometry Learn how to use trig functions to find an unknown side length in a right triangle. article https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-solve-for-an-angle/a/inverse-trig-functions-intro 2026-03-05T14:30:38.694195715Z Intro to inverse trig functions Learn about arcsine, arccosine, and arctangent, and how they can be used to solve for a missing angle in right triangles. article https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-solve-for-a-side/e/trigonometry_2 2025-03-09T12:38:48.303569754Z Solve for a side in right triangles Given one side length and an acute angle in a right triangle, find another side using trigonometry. Tomer Gal exercise https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-solve-for-an-angle/e/solve-for-an-angle-in-a-right-triangle 2024-09-04T17:59:01.633715485Z Solve for an angle in right triangles Given two sides in a right triangle, find one of the acute angles using trigonometry. Tomer Gal exercise https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-modeling-with-right-triangles/v/angle-to-aim-to-get-alien 2021-06-30T17:32:40Z Right triangle word problem Sal solves a modeling problem where he finds the necessary angle to shoot at a vicious alien. Sal Khan video https://cdn.kastatic.org/googleusercontent/dlKu1szoXgEqwAoKxoMQLwa9LQVPo-o5Xt6xJ7m4NixSAhQDy0ixvWC3z9NTDTrLNi4qYlA-wQGTGhmRy0ab_ypT Right triangle word problem Sal solves a modeling problem where he finds the necessary angle to shoot at a vicious alien. https://cdn.kastatic.org/ka-youtube-converted/aHzd-u35LuA.mp4/aHzd-u35LuA.mp4 275 Trigonometry https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-modeling-with-right-triangles/a/angles-of-elevation-and-depression 2022-09-10T02:03:40.164764806Z Angles of elevation and depression Learn what  the terms angle of elevation and angle of depression mean. The words may be big but their meaning is pretty basic! article https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-modeling-with-right-triangles/a/right-triangle-trigonometry-review 2024-11-10T11:54:31.281000574Z Right triangle trigonometry review Review right triangle trigonometry and how to use it to solve problems. article https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-modeling-with-right-triangles/e/applying-right-triangles 2026-04-08T01:15:04.085520103Z Right triangle trigonometry word problems Solve word problems by modeling real-world (and not-so-real) situations as right triangles and using trigonometry. Tomer Gal exercise