Advertisements
Advertisements
рдкреНрд░рд╢реНрди
If x=a `cos^3 theta and y = b sin ^3 theta ," prove that " (x/a)^(2/3) + ( y/b)^(2/3) = 1.`
рдЙрддреНрддрд░
We have x = a `cos^3 theta `
= > `x/a = cos^3 theta ........(i)`
Again , `y = b sin^3 theta`
= > `y/b = sin^3 theta .....(ii)`
Now , LHS = `(x/a)^(2/3) + (y/b)^(2/3)`
= `( cos^3 theta )^(2/3) + (sin^3 theta )^ (2/3 )` [ from (i) and (ii)]
=` cos^2 theta + sin^2 theta `
=1
ЁЭР╗ЁЭСТЁЭСЫЁЭСРЁЭСТ, ЁЭР┐ЁЭР╗ЁЭСЖ = ЁЭСЕЁЭР╗ЁЭСЖ
APPEARS IN
рд╕рдВрдмрдВрдзрд┐рдд рдкреНрд░рд╢реНрди
Prove the following identities:
`(i) 2 (sin^6 θ + cos^6 θ) –3(sin^4 θ + cos^4 θ) + 1 = 0`
`(ii) (sin^8 θ – cos^8 θ) = (sin^2 θ – cos^2 θ) (1 – 2sin^2 θ cos^2 θ)`
If m=(acosθ + bsinθ) and n=(asinθ – bcosθ) prove that m2+n2=a2+b2
Prove the following trigonometric identities.
`1 + cot^2 theta/(1 + cosec theta) = cosec theta`
Prove the following trigonometric identities.
(sec A + tan A − 1) (sec A − tan A + 1) = 2 tan A
Prove the following identities:
sec2 A . cosec2 A = tan2 A + cot2 A + 2
Prove the following identities:
`1/(sinA + cosA) + 1/(sinA - cosA) = (2sinA)/(1 - 2cos^2A)`
Prove that:
`sqrt(sec^2A + cosec^2A) = tanA + cotA`
If ` cot A= 4/3 and (A+ B) = 90° ` ,what is the value of tan B?
Write the value of tan10° tan 20° tan 70° tan 80° .
If \[\sin \theta = \frac{1}{3}\] then find the value of 2cot2 θ + 2.
2 (sin6 θ + cos6 θ) − 3 (sin4 θ + cos4 θ) is equal to
Prove the following identity :
`(sinA + cosA)/(sinA - cosA) + (sinA - cosA)/(sinA + cosA) = 2/(2sin^2A - 1)`
If x = r sinA cosB , y = r sinA sinB and z = r cosA , prove that `x^2 + y^2 + z^2 = r^2`
If secθ + tanθ = m , secθ - tanθ = n , prove that mn = 1
Prove that tan2Φ + cot2Φ + 2 = sec2Φ.cosec2Φ.
Prove that sin (90° - θ) cos (90° - θ) = tan θ. cos2θ.
Prove the following identities.
`sqrt((1 + sin theta)/(1 - sin theta)) + sqrt((1 - sin theta)/(1 + sin theta))` = 2 sec θ
Prove the following identities.
sec6 θ = tan6 θ + 3 tan2 θ sec2 θ + 1
If 1 + sin2α = 3 sinα cosα, then values of cot α are ______.
Given that sinθ + 2cosθ = 1, then prove that 2sinθ – cosθ = 2.