Answer:
Let θ = (45 - A)°.
=> 2Tanθ/ 1 + Tan²θ
=> 2Sinθ/Cosθ / 1 + Sin²θ / Cos²θ
=> 2Sinθ/Cosθ/ Cos²θ + Cos²θ / Cos²θ
=> 2Sinθ/Cosθ/ 1 / Cos²θ
=> 2SinθCos²θ/Cosθ
=> 2SinθCosθ
=> Sin2θ
But we assumed θ = (45 - A)°,
=> Sin2(45 - A)
=> Sin(90 - 2A) (∵ Sin(90 - θ) = Cosθ)
=> Cos2A
= R.H.S
Hence proved.
Step-by-step explanation:
Answer:
2 numbers could be 10 and 12
or - 12 and - 10
Step-by-step explanation:
let the 2 numbers be x and x + 2
since they are 2 consecutive even numbers, the difference between them is 2
the difference between the reciprocals is 1/60
we have to mulitply the 2 denominators x and (x+2) to get a common denominator for the 2 fractions
=
we can then remove the brackets from the numerator and denominator
and then cross multiply
60 * 2 = x² + 2x
120 = x² + 2x
x² + 2x - 120 = 0
we have a quadratic equation which needs to be solved
x² + 12x - 10x - 120 = 0
x (x + 12) - 10(x + 12) = 0
(x - 10) (x + 12) = 0
x - 10 = 0 or x + 12 = 0
x = 10 x = -12
like horror movies hate horror movies total
like animated 21 22 43
doesn't like animated 56 3 59
total 77 25 102
if a student likes horror movies (there are 77 of them)...what is the probability that student also like animated movies.....21/77 or 27%
Answer:
The missing number is 150
Step-by-step explanation:
45 + 5= ? -100
To carry out the problem we are going to call x to (?)
45 + 5= x -100
we see that we have a -100 of the second side of the equality, to get it out of there we can add 100 in both parts of the equality
45 + 5 + 100 = x -100 + 100
now we just solve and we have left
45 + 5 + 100 = x
As we see this is a common sum, by which we can already add it and obtain the value of x
150 = x
