Question

if cos 9alpha=sin alpha and 9alpha is greater than 90degree find the value of tan5 alpha​

Answer 1

Answer:

Step-by-step explanation:

Given,

            Cos9α =Sinα

 ⇒         Sin(90 - 9α) = sinα                                         (∵ Cos a = sin (90- a)  )

 ⇒         90 - 9α = α    ⇒ 10α = 90

  ⇒         α = 9

             Tan 5α = Tan 5 × 9 = Tan 45° = 1

Answer 2

$\huge\mathfrak{Bonjour!!}$

$\huge\fcolorbox{black}{aqua}{Solution:-}$

✒ ᴀɴsᴡᴇʀ:-

⛄ тαη 5α = 1

✒ sᴛᴇᴘ-ʙʏ-sᴛᴇᴘ ᴇxᴘʟᴀɴᴀᴛɪᴏɴ:-

⛄ ωє нαѵє,

cσs 9α = sıη α

⇝cσs 9α = cσs (90° - α)

ση cσмραяıηg вσтн тнє sı∂єs, ωє нαѵє

9α = 90° - α

⇝10α = 90°

⇝α = 9°

∴ тαη 5α = тαη 5 × 9° = тαη 45° = 1

___________________________

♥í հօթҽ Եհís հҽlթs!❤