Math, asked by dii, 1 year ago

if tan a + cot a =2 then find the value of tan2 a + cot 2 a

Answers

Answered by abhi178
578
tana + cota =2
take square both sides
(tana + cota)² = 2²
tan²a + cot²a +2tana.cota =4

we Know,
tana =1/cota
so,
tan² a + cot²a +2 = 4
tan²a + cot² a = 4 -2 = 2

Anonymous: Is it correct?
sumasree1111: yes
Anonymous: then who reported it'
Answered by Anonymous
63

Question :-

If tan a + cot a = 2 , then find the value of tan²a + cot²a .

[ Let a = ∅ ]

▶ Answer :-

→ tan²∅ + cot²∅ = 2 .

▶ Step-by-step explanation :-

Given :-

→ tan ∅ + cot ∅ = 2 .

➡ To find :-

→ tan²∅ + cot²∅ .

 \huge \pink{ \mid \underline{ \overline{ \sf Solution :- }} \mid}

We have ,

 \begin{lgathered}\sf \because \tan \theta + \cot \theta = 2. \\ \\ \sf \implies \tan \theta + \frac{1}{ \tan \theta} = 2. \\ \\ \sf \implies \frac{ { \tan}^{2} \theta + 1}{ \tan \theta} = 2. \\ \\ \sf \implies { \tan}^{2} \theta + 1 = 2 \tan \theta. \\ \\ \sf \implies { \tan}^{2} \theta - 2 \tan \theta + 1 = 0. \\ \\ \sf \implies {( \tan \theta - 1)}^{2} = 0. \\ \\ \bigg( \sf \because {(a - b)}^{2} = {a}^{2} - 2ab + {b}^{2} . \bigg) \\ \\ \sf \implies \tan \theta - 1 = \sqrt{0} . \\ \\ \sf \implies \tan \theta - 1 = 0. \\ \\ \: \: \: \: \large \green{\sf \therefore \tan \theta = 1.}\end{lgathered}

Now,

→ To find :-

 \begin{lgathered}\sf \because { \tan}^{2} \theta + { \cot}^{2} \theta . \\ \\ \sf = { \tan}^{2} \theta + \frac{1}{ { \tan}^{2} \theta } . \\ \\ \sf = {1}^{2} + \frac{1}{ {1}^{2} } . \: \: \: \: \bigg( \green{\because \tan \theta = 1}. \bigg) \\ \\ \sf = 1 + 1. \\ \\ \huge \boxed{ \boxed{ \orange{ = 2.}}}\end{lgathered}

✔✔ Hence, it is solved ✅✅.

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