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Question
Choose the correct alternative:
Which is not correct formula?
Options
1 + tan2θ = sec2θ
1 + sec2θ = tan2θ
cosec2θ − cot2θ = 1
sin2θ + cos2θ = 1
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Solution
1 + sec2θ = tan2θ
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RELATED QUESTIONS
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1 + cot2θ = ?
Choose the correct alternative:
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If tan θ = `9/40`, complete the activity to find the value of sec θ.
Activity:
sec2θ = 1 + `square` ......[Fundamental trigonometric identity]
sec2θ = 1 + `square^2`
sec2θ = 1 + `square`
sec θ = `square`
tan2θ – sin2θ = tan2θ × sin2θ. For proof of this complete the activity given below.
Activity:
L.H.S = `square`
= `square (1 - (sin^2theta)/(tan^2theta))`
= `tan^2theta (1 - square/((sin^2theta)/(cos^2theta)))`
= `tan^2theta (1 - (sin^2theta)/1 xx (cos^2theta)/square)`
= `tan^2theta (1 - square)`
= `tan^2theta xx square` .....[1 – cos2θ = sin2θ]
= R.H.S
Prove the following:
`tanA/(1 + sec A) - tanA/(1 - sec A)` = 2cosec A
Statement 1: sin2θ + cos2θ = 1
Statement 2: cosec2θ + cot2θ = 1
Which of the following is valid?
