Advertisements
Advertisements
प्रश्न
Evaluate the following
sin2 30° + sin2 45° + sin2 60° + sin2 90°
Advertisements
उत्तर
sin2 30° + sin2 45° + sin2 60° + sin2 90° .....(1)
`sin 30^@ = 1/2 sin 45^@ = 1/sqrt2`
`sin 60^@ = sqrt3/2 sin 90^@ = 1`
By substituting above values in (i), we get
`= [1/2]^2 + [1/sqrt2]^2 + [sqrt3/2]^2 + [1]^2`
`= 1/4 + 1/2 + 3/4 + 1 => (1 + 3)/4 + (1 + 2)/2`
`=> 1 + 3/2 = (2 + 3)/2 = 5/2`
APPEARS IN
संबंधित प्रश्न
In the following, one of the six trigonometric ratios is given. Find the values of the other trigonometric ratios.
`tan alpha = 5/12`
In the following, one of the six trigonometric ratios is given. Find the values of the other trigonometric ratios.
`tan theta = 8/15`
In the following, trigonometric ratios are given. Find the values of the other trigonometric ratios.
`sec theta = 13/5`
If `sec θ = 13/5`, show that `(2 sin θ - 3 cos θ)/(4 sin θ - 9 cos θ) = 3`.
If sin θ = `12/13`, Find `(sin^2 θ - cos^2 θ)/(2sin θ cos θ) × 1/(tan^2 θ)`.
Evaluate the Following
4(sin4 60° + cos4 30°) − 3(tan2 60° − tan2 45°) + 5 cos2 45°
Evaluate the Following
(cos 0° + sin 45° + sin 30°)(sin 90° − cos 45° + cos 60°)
Evaluate the Following:
`tan 45^@/(cosec 30^@) + sec 60^@/cot 45^@ - (5 sin 90^@)/(2 cos 0^@)`
Find the value of x in the following :
`2sin 3x = sqrt3`
Find the value of x in the following :
`2 sin x/2 = 1`
If A and (2A – 45°) are acute angles such that sin A = cos (2A – 45°), then tan A is equal to ______.
If sin θ + sin² θ = 1, then cos² θ + cos4 θ = ______.
If 4 tanθ = 3, then `((4 sintheta - costheta)/(4sintheta + costheta))` is equal to ______.
Prove that sec θ + tan θ = `cos θ/(1 - sin θ)`.
Proof: L.H.S. = sec θ + tan θ
= `1/square + square/square`
= `square/square` ......`(∵ sec θ = 1/square, tan θ = square/square)`
= `((1 + sin θ) square)/(cos θ square)` ......[Multiplying `square` with the numerator and denominator]
= `(1^2 - square)/(cos θ square)`
= `square/(cos θ square)`
= `cos θ/(1 - sin θ)` = R.H.S.
∴ L.H.S. = R.H.S.
∴ sec θ + tan θ = `cos θ/(1 - sin θ)`
Find the value of sin 45° + cos 45° + tan 45°.
If θ is an acute angle and sin θ = cos θ, find the value of tan2 θ + cot2 θ – 2.
In a right triangle PQR, right angled at Q. If tan P = `sqrt(3)`, then evaluate 2 sin P cos P.

In ΔBC, right angled at C, if tan A = `8/7`, then the value of cot B is ______.

