Advertisements
Advertisements
Question
If tanθ = 2, find the values of other trigonometric ratios.
Solution
tanθ = 2 ...(Given)
∴ cotθ = `1/2`
We have,
1 + tan2θ = sec2θ
1 + (2)2 = sec2θ
1 + 4 = sec2θ
5 = sec2θ
Taking Square root on both sides
secθ = `sqrt5`
Cosθ = `1/secθ`
Cosθ = `1/sqrt5`
tanθ = `sinθ/cosθ`
2 = `sinθ/(1/sqrt5)`
2 = `sinθ xx sqrt5/1`
`2/sqrt5 = sinθ`
`sinθ = 2/sqrt5`
cosecθ = `1/sinθ`
= `1/(2/sqrt5)`
= `1 xx sqrt5/2`
∴ cosecθ = `sqrt5/2`
RELATED QUESTIONS
If sin θ =3/5, where θ is an acute angle, find the value of cos θ.
`\text{Evaluate }\frac{\tan 65^\circ }{\cot 25^\circ}`
Without using trigonometric tables, evaluate the following:
`( i)\frac{\cos37^\text{o}}{\sin53^\text{o}}\text{ }(ii)\frac{\sin41^\text{o}}{\cos 49^\text{o}}(iii)\frac{\sin30^\text{o}17'}{\cos59^\text{o}\43'}`
Solve.
`sec75/(cosec15)`
Evaluate.
`(sin77^@/cos13^@)^2+(cos77^@/sin13^@)-2cos^2 45^@`
Evaluate.
`cos^2 26^@+cos65^@sin26^@+tan36^@/cot54^@`
Evaluate:
tan(55° - A) - cot(35° + A)
Find the value of x, if cos x = cos 60° cos 30° – sin 60° sin 30°
Use tables to find cosine of 26° 32’
Prove that:
sec (70° – θ) = cosec (20° + θ)
If A and B are complementary angles, prove that:
cot A cot B – sin A cos B – cos A sin B = 0
If 4 cos2 A – 3 = 0 and 0° ≤ A ≤ 90°, then prove that sin 3 A = 3 sin A – 4 sin3 A
Find A, if 0° ≤ A ≤ 90° and 4 sin2 A – 3 = 0
If 3 cot θ = 4, find the value of \[\frac{4 \cos \theta - \sin \theta}{2 \cos \theta + \sin \theta}\]
Write the value of tan 10° tan 15° tan 75° tan 80°?
If x tan 45° cos 60° = sin 60° cot 60°, then x is equal to
Prove that:
(sin θ + 1 + cos θ) (sin θ − 1 + cos θ) . sec θ cosec θ = 2
A, B and C are interior angles of a triangle ABC. Show that
sin `(("B"+"C")/2) = cos "A"/2`
Express the following in term of angles between 0° and 45° :
sin 59° + tan 63°
If A, B and C are interior angles of a ΔABC then `cos (("B + C")/2)` is equal to ______.