Question

if sim Q=4/5then fined cosQ
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Answer 1

Answer:

Given,

sin Q = 4/5

=> p/h = 4/5 ( here, p= perpendicular and h= hypotenuse)

=> p/4 = h/5 = k (say)

=>p= 4k, h= 5k

Now, by Pythagoras theorem-----

h²= p²+b²

=> (5k)² = (4k)² + b²

=> 25k² = 16k² + b²

=> 25k² - 16k² = b²

=> 9k²= b²

=>b²= 9k²

=> b= 3k

Therefore,

cos Q = b/h

= 3k/5k

= 3/5