Advertisements
Advertisements
Question
Prove that secθ + tanθ =`(costheta)/(1-sintheta)`.
Solution
secθ + tanθ = `1/cosθ + sintheta/cosθ`
`=(1+sintheta)/costheta`
`=((1+sintheta)(1-sintheta))/(costheta (1-sintheta))`
`=(1^2 - sin^2theta)/(costheta(1-sintheta))`
`=cos^2theta/(costheta(1-sintheta))`
`therefore sectheta +tantheta =costheta/(1-sintheta)`
APPEARS IN
RELATED QUESTIONS
Prove the following identities, where the angles involved are acute angles for which the expressions are defined:
`cos A/(1 + sin A) + (1 + sin A)/cos A = 2 sec A`
Prove that `(sin theta)/(1-cottheta) + (cos theta)/(1 - tan theta) = cos theta + sin theta`
Prove the following trigonometric identities.
sec6θ = tan6θ + 3 tan2θ sec2θ + 1
Prove the following identities:
`1/(1 - sinA) + 1/(1 + sinA) = 2sec^2A`
Prove the following identities:
`(1 + sinA)/cosA + cosA/(1 + sinA) = 2secA`
Prove the following identities:
`(cotA - cosecA)^2 = (1 - cosA)/(1 + cosA)`
Prove the following identities:
`cosA/(1 - sinA) = sec A + tan A`
If `cosA/cosB = m` and `cosA/sinB = n`, show that : (m2 + n2) cos2 B = n2.
Prove that:
(tan A + cot A) (cosec A – sin A) (sec A – cos A) = 1
cosec4θ − cosec2θ = cot4θ + cot2θ
If `sqrt(3) sin theta = cos theta and theta ` is an acute angle, find the value of θ .
`If sin theta = cos( theta - 45° ),where theta " is acute, find the value of "theta` .
Prove the following identities:
`(sec"A"-1)/(sec"A"+1)=(sin"A"/(1+cos"A"))^2`
Prove the following identity :
`1/(cosA + sinA - 1) + 2/(cosA + sinA + 1) = cosecA + secA`
If `x/(a cosθ) = y/(b sinθ) "and" (ax)/cosθ - (by)/sinθ = a^2 - b^2 , "prove that" x^2/a^2 + y^2/b^2 = 1`
If x = r sinA cosB , y = r sinA sinB and z = r cosA , prove that `x^2 + y^2 + z^2 = r^2`
Find x , if `cos(2x - 6) = cos^2 30^circ - cos^2 60^circ`
Without using trigonometric identity , show that :
`tan10^circ tan20^circ tan30^circ tan70^circ tan80^circ = 1/sqrt(3)`
If A = 30°, verify that `sin 2A = (2 tan A)/(1 + tan^2 A)`.
Prove that sin θ sin( 90° - θ) - cos θ cos( 90° - θ) = 0