Advertisements
Advertisements
Question
Prove the following:
`sin^-1(3/5) + cos^-1(12/13) = sin^-1(56/65)`
Solution
Let `sin^-1(3/5) = x, cos^-1(12/13) = y and sin^-1(56/65)` = z.
Then `sin x = (3)/(5), "where" 0 < x < pi/(2)`
cos y = `(12)/(13), "where" 0 < y < pi/(2)`
and sin z = `(56)/(65), "where" 0 < z < pi/(2)`
∴ cos x > 0, sin y > 0
Finding sin x, cos x
Now, cos x = `sqrt(1 - sin^2 x)`
= `sqrt(1 - ((3)/(5))^2 `
= `sqrt(1 - (9)/(25)` = `sqrt(16/25) = (4)/(5)`
Finding sin y, cos y
sin y = `sqrt(1 - cos^2y)`
= `sqrt(1 - ((12)/(13))^2`
= `sqrt(1 - (144)/(169)` = `sqrt(25/169) = (5)/(13)`
We know that
`sin(x + y) = sin x cos y + cos x sin y`
= `(3/5) "x" (12/13) + (4/5) "x" (5/13)`
= `(36)/(65) + (20)/(65) = (56)/(65)`
`∴ sin(x + y) = (56)/(65)`
`∴ x + y = sin^-1 (56)/(65)`
Hence, `sin^-1(3/5) + cos^-1(12/13) = sin^-1(56/65)`.
APPEARS IN
RELATED QUESTIONS
If `sin^-1(1-x) -2sin^-1x = pi/2` then x is
- -1/2
- 1
- 0
- 1/2
Find the principal value of `tan^(-1) (-sqrt3)`
Find the principal value of `sec^(-1) (2/sqrt(3))`
Find the principal value of `cosec^(-1)(-sqrt2)`
Find the value of the following:
If sin−1 x = y, then
Prove that:
`tan^-1 ((sqrt(1 + x) - sqrt(1 - x))/(sqrt(1 + x) + sqrt(1 - x))) = pi/4 - 1/2 cos^-1 x`, for `- 1/sqrt2 <= x <= 1`
[Hint: put x = cos 2θ]
`sin^-1 1/2-2sin^-1 1/sqrt2`
`sin^-1{cos(sin^-1 sqrt3/2)}`
Find the domain of the following function:
`f(x)=sin^-1x^2`
Find the domain of the following function:
`f(x)sin^-1sqrt(x^2-1)`
Find the domain of `f(x)=cotx+cot^-1x`
Evaluate the following:
`tan^-1(-1/sqrt3)+cot^-1(1/sqrt3)+tan^-1(sin(-pi/2))`
Evaluate: tan `[ 2 tan^-1 (1)/(2) – cot^-1 3]`
In ΔABC, if a = 18, b = 24, c = 30 then find the values of A(ΔABC)
In ΔABC, if a = 18, b = 24, c = 30 then find the values of sinA
Find the principal value of the following: sin-1 `(1/sqrt(2))`
Evaluate the following:
`tan^-1(1) + cos^-1(1/2) + sin^-1(1/2)`
Prove the following:
`sin^-1(-1/2) + cos^-1(-sqrt(3)/2) = cos^-1(-1/2)`
sin−1x − cos−1x = `pi/6`, then x = ______
Find the value of `cos^-1 (1/2) + tan^-1 (1/sqrt(3))`
Evaluate `cos[pi/6 + cos^-1 (- sqrt(3)/2)]`
Prove that cot−1(7) + 2 cot−1(3) = `pi/4`
Prove that `2 tan^-1 (1/8) + tan^-1 (1/7) + 2tan^-1 (1/5) = pi/4`
Find the principal value of the following:
cosec-1 (2)
Show that `tan^-1 (1/2) + tan^-1 (2/11) = tan^-1 (3/4)`
A man standing directly opposite to one side of a road of width x meter views a circular shaped traffic green signal of diameter ‘a’ meter on the other side of the road. The bottom of the green signal Is ‘b’ meter height from the horizontal level of viewer’s eye. If ‘a’ denotes the angle subtended by the diameter of the green signal at the viewer’s eye, then prove that α = `tan^-1 (("a" + "b")/x) - tan^-1 ("b"/x)`
Choose the correct alternative:
cos 2θ cos 2ϕ+ sin2 (θ – ϕ) – sin2 (θ + ϕ) is equal to
sin[3 sin-1 (0.4)] = ______.
If `sin^-1x + cos^-1y = (3pi)/10,` then `cos^-1x + sin^-1y =` ______
If `sin^-1 3/5 + cos^-1 12/13 = sin^-1 P`, then P is equal to ______
If sin `(sin^-1 1/3 + cos^-1 x) = 1`, then the value of x is ______.
`sin{tan^-1((1 - x^2)/(2x)) + cos^-1((1 - x^2)/(1 + x^2))}` is equal to ______
The value of `sin^-1[cos(pi/3)] + sin^-1[tan((5pi)/4)]` is ______.
The domain of the function defined by f(x) = sin–1x + cosx is ______.
The equation tan–1x – cot–1x = `(1/sqrt(3))` has ______.
Prove that `cot(pi/4 - 2cot^-1 3)` = 7
Prove that `tan^-1 1/4 + tan^-1 2/9 = sin^-1 1/sqrt(5)`
All trigonometric functions have inverse over their respective domains.
`("cos" 8° - "sin" 8°)/("cos" 8° + "sin" 8°)` is equal to ____________.
If `"sin"^-1("x"^2 - 7"x" + 12) = "n"pi, AA "n" in "I"`, then x = ____________.
`"sin"^-1 (-1/2)`
`"tan"^-1 (sqrt3)`
`"sin"^-1 (1/sqrt2)`
If tan-1 (x – 1) + tan-1 x + tan-1 (x + 1) = tan-1 3x, then the values of x are ____________.
`"sin" ["cot"^-1 {"cos" ("tan"^-1 "x")}] =` ____________.
The value of `"cos"^-1 ("cos" ((33 pi)/5))` is ____________.
`"cos"^-1 ["cos" (2 "cot"^-1 (sqrt2 - 1))] =` ____________.
The range of sin-1 x + cos-1 x + tan-1 x is ____________.
Find the value of sec2 (tan-1 2) + cosec2 (cot-1 3) ____________.
The equation 2cos-1 x + sin-1 x `= (11pi)/6` has ____________.
`sin[π/3 - sin^-1 (-1/2)]` is equal to:
`2"tan"^-1 ("cos x") = "tan"^-1 (2 "cosec x")`
If |Z1| = |Z2| and arg (Z1) + arg (Z2) = 0, then
What is the value of `sin^-1(sin (3pi)/4)`?
Domain and Rariges of cos–1 is:-
What will be the principal value of `sin^-1(-1/2)`?
Find the principal value of `tan^-1 (sqrt(3))`
Values of tan–1 – sec–1(–2) is equal to
`sin(tan^-1x), |x| < 1` is equal to
What is the values of `cos^-1 (cos (7pi)/6)`
If `sin(sin^-1 1/5 + cos^-1 x) = 1`, the what will be the value of x?
If f'(x) = x–1, then find f(x)
If θ = `sin^-1((2x)/(1 + x^2)) + cos^-1((1 - x^2)/(1 + x^2))`, for `x ≥ 3/2` then the absolute value of `((cosθ + tanθ + 4)/secθ)` is ______.
Number of values of x satisfying the system of equations `sin^-1sqrt(2 + e^(-2x) - 2e^-x) + sec^-1sqrt(1 - x^2 + x^4) = π/2` and `5^(1+tan^-1x)` = 4 + [cos–1x] is ______ (where [.] denotes greatest integer function)
Number of values of x which lie in [0, 2π] and satisfy the equation
`(cos x/4 - 2sinx) sinx + (1 + sin x/4 - 2cosx)cosx` = 0
If sin–1a + sin–1b + sin–1c = π, then find the value of `asqrt(1 - a^2) + bsqrt(1 - b^2) + csqrt(1 - c^2)`.
If tan–1 2x + tan–1 3x = `π/4`, then x = ______.
If cos–1 x > sin–1 x, then ______.
If –1 ≤ x ≤ 1, the prove that sin–1 x + cos–1 x = `π/2`
Prove that:
tan–1x + tan–1y = `π + tan^-1((x + y)/(1 - xy))`, provided x > 0, y > 0, xy > 1
Solve for x:
5tan–1x + 3cot–1x = 2π