Pythagoras and Trigonometry: The Sine and Cosine Rules

The video tutorial explains how to find the largest angle in a triangle with sides of 8 cm, 10 cm, and 14 cm using trigonometry. It involves sketching the triangle, identifying the largest angle opposite the longest side, and applying the cosine rule. The tutorial details substituting side lengths into the formula, calculating the cosine of the angle, and using the inverse cosine function to find the angle, which is approximately 101.5 degrees. The video concludes with a recap and explanation of the marks allocation for the problem.

What is the calculated value of cosA before finding the angle?

How do you find the angle A using the value of cosA?

What is the final answer for the largest angle of the triangle, correct to one decimal place?