Advertisements
Advertisements
Question
Evaluate the following
`sin^2 30° cos^2 45 ° + 4 tan^2 30° + 1/2 sin^2 90° − 2 cos^2 90° + 1/24 cos^2 0°`
Advertisements
Solution
`sin^2 30° cos^2 45 ° + 4 tan^2 30° + 1/2 sin^2 90° − 2 cos^2 90° + 1/24 cos^2 0°` ....(i)
By trigonometric ratios we have
`sin 30^@ = 1/2` `cos 45^@ = 1/sqrt2` `tan 30^2 = 1/sqrt3` `sin 90^@ = 1 cos 90^@ = 0 cos 0^@ = 1`
By substituting above values in (i), we get
`[1/2]^2 . [1/sqrt2]^2 + 4[1/sqrt3]^2 + 1/2[1]^2 - 2[0]^2 + 1/24 [1]^2`
`1/4.1/2 + 4/ 1/3 + 1/2 - 0 + 1/24`
`1/8 + 4/3 + 1/2 + 1/24 = 48/24 = 2`
RELATED QUESTIONS
In ΔABC right angled at B, AB = 24 cm, BC = 7 m. Determine:
sin C, cos C
In Given Figure, find tan P – cot R.

Prove that `(sin "A" - 2sin^3 "A")/(2cos^3 "A" - cos "A") = tan "A"`
In the following, trigonometric ratios are given. Find the values of the other trigonometric ratios.
`sin A = 2/3`
In the following, one of the six trigonometric ratios is given. Find the values of the other trigonometric ratios.
`cot theta = 12/5`
In the following, one of the six trigonometric ratios is given. Find the values of the other trigonometric ratios.
`cos theta = 12/2`
Evaluate the following
cos 60° cos 45° - sin 60° ∙ sin 45°
Evaluate the following
tan2 30° + tan2 60° + tan2 45°
Evaluate the following
`2 sin^2 30^2 - 3 cos^2 45^2 + tan^2 60^@`
Find the value of x in the following :
`sqrt3 sin x = cos x`
Find the value of x in the following :
cos 2x = cos 60° cos 30° + sin 60° sin 30°
If sin (A − B) = sin A cos B − cos A sin B and cos (A − B) = cos A cos B + sin A sin B, find the values of sin 15° and cos 15°.
sin (45° + θ) – cos (45° – θ) is equal to ______.
`(1 + tan^2 "A")/(1 + cot^2 "A")` is equal to ______.
Given that sinα = `1/2` and cosβ = `1/2`, then the value of (α + β) is ______.
Prove the following:
If tan A = `3/4`, then sinA cosA = `12/25`
Find an acute angle θ when `(cos θ - sin θ)/(cos θ + sin θ) = (1 - sqrt(3))/(1 + sqrt(3))`
If θ is an acute angle of a right angled triangle, then which of the following equation is not true?
Evaluate: 5 cosec2 45° – 3 sin2 90° + 5 cos 0°.
