Advertisements
Advertisements
प्रश्न
If x = a cos θ and y = b sin θ, then b2x2 + a2y2 =
विकल्प
a2 b2
ab
a4 b4
a2 + b2
उत्तर
Given:
`x= a cosθ, y= b sin θ`
So,
`b^2 x^2+a^2 y^2`
= `b^2(a cos)^2+a^2(b sin θ)^2`
=` b^2 a^2 cos^2θ+a^2 b^2 sin^2θ`
=`b^2a^2 (cos^2 θ+sin^2θ)`
We know that,
`sin^2θ+cos^2θ=1`
Therefore,` b^2x^2+a^2y^2=a^2b^2`
APPEARS IN
संबंधित प्रश्न
Evaluate
`(sin ^2 63^@ + sin^2 27^@)/(cos^2 17^@+cos^2 73^@)`
Without using trigonometric tables evaluate
`(sin 35^@ cos 55^@ + cos 35^@ sin 55^@)/(cosec^2 10^@ - tan^2 80^@)`
Prove the following trigonometric identities.
`tan theta - cot theta = (2 sin^2 theta - 1)/(sin theta cos theta)`
Prove the following trigonometric identities.
sin2 A cos2 B − cos2 A sin2 B = sin2 A − sin2 B
Show that : `sinAcosA - (sinAcos(90^circ - A)cosA)/sec(90^circ - A) - (cosAsin(90^circ - A)sinA)/(cosec(90^circ - A)) = 0`
Prove that:
`1/(sinA - cosA) - 1/(sinA + cosA) = (2cosA)/(2sin^2A - 1)`
`sin^2 theta + cos^4 theta = cos^2 theta + sin^4 theta`
cosec4θ − cosec2θ = cot4θ + cot2θ
`(sec theta + tan theta )/( sec theta - tan theta ) = ( sec theta + tan theta )^2 = 1+2 tan^2 theta + 25 sec theta tan theta `
`(cot^2 theta ( sec theta - 1))/((1+ sin theta))+ (sec^2 theta(sin theta-1))/((1+ sec theta))=0`
Prove that:
`(sin^2θ)/(cosθ) + cosθ = secθ`
Prove the following identity :
`(cosecA - sinA)(secA - cosA) = 1/(tanA + cotA)`
Prove the following identity :
`(cotA + tanB)/(cotB + tanA) = cotAtanB`
Prove the following identity :
`(cot^2θ(secθ - 1))/((1 + sinθ)) = sec^2θ((1-sinθ)/(1 + secθ))`
If `asin^2θ + bcos^2θ = c and p sin^2θ + qcos^2θ = r` , prove that (b - c)(r - p) = (c - a)(q - r)
If cosθ = `5/13`, then find sinθ.
Prove that: 2(sin6θ + cos6θ) - 3 ( sin4θ + cos4θ) + 1 = 0.
Prove that `(sin 70°)/(cos 20°) + (cosec 20°)/(sec 70°) - 2 cos 70° xx cosec 20°` = 0.
If 5 sec θ – 12 cosec θ = 0, then find values of sin θ, sec θ
Prove that `sec"A"/(tan "A" + cot "A")` = sin A