Question

Given ∆ABC right angled at C in which AB = 29 units BC = 21 units and <ABC = theta . Determine the value of
$\cos {}^{2}$ theta + $\sin {}^{2}$theta​

Answer 1

Answer:

1

Step-by-step explanation:

we know, according to Pythagoras theorem ,

AB² = AC² +BC²

⇒ AC²  = AB² - BC²

⇒ AC=√(AB² -BC²)

⇒ AC=√(29² -21² ) =20 unit

Then,

sin∅ = AC/AB = 20/29

cos∅ =BC/AB = 21/29

Now,

sin²∅ +cos²∅

=> (20²+21²)/29²

=> 1

Hope it helps!