Advertisements
Advertisements
प्रश्न
Evaluate: sin`[1/2 cos^-1 (4/5)]`
उत्तर
Let `cos^-1 (4/5)` = A
Then `4/5` = cos A
cos A = `4/5`
∴ `sin [1/2 cos^-1 (4/5)] = sin (1/2 "A") = sin "A"/2`
We know that
cos A = 1 - 2 sin2 `"A"/2`
`4/5 = 1 - 2 sin^2 "A"/2`
`2 sin^2 "A"/2 = 1 - 4/5`
`2 sin^2 "A"/2 = 1/5`
∴ `sin^2 "A"/2 = 1/10`
∴ `sin "A"/2 = 1/sqrt10`
APPEARS IN
संबंधित प्रश्न
Find the principal value of cosec−1 (2)
Find the domain of the following function:
`f(x) = sin^-1x + sinx`
In ΔABC, if a = 18, b = 24, c = 30 then find the values of cos `A/2`
Find the principal value of the following: `sin^-1 (1/2)`
`tan^-1(tan (7pi)/6)` = ______
If sin `(sin^-1 1/3 + cos^-1 x) = 1`, then the value of x is ______.
Prove that `cot(pi/4 - 2cot^-1 3)` = 7
If `"x" in (- pi/2, pi/2), "then the value of tan"^-1 ("tan x"/4) + "tan"^-1 ((3 "sin" 2 "x")/(5 + 3 "cos" 2 "x"))` is ____________.
If A = `[(cosx, sinx),(-sinx, cosx)]`, then A1 A–1 is
If |Z1| = |Z2| and arg (Z1) + arg (Z2) = 0, then