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Proof the given identity.
sec^2 x = 1 + tan^2 x
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Answer:
Starting from:
cos2(x)+sin2(x)=1
Divide both sides by cos2(x) to get:
cos2(x)cos2(x)+sin2(x)cos2(x)=1cos2(x)
which simplifies to:
1+tan2(x)=sec2(x)
Answer:
Step-by-step explanation:
[tex]\sf{sec^2 x = 1+ tan^2 x}[/tex]
For this, we will first simplify RHS to get back LHS.
Here, we go towards right, the right path:-
We know that:-
[tex]\sf{tanx = \dfrac{sinx}{cosx}}[/tex]—-(1)
And, we also know this one :-
[tex]\sf{secx = \dfrac{1}{cosx}}[/tex] ——(2)
Let’s start the mechanism to get the resultant.
[tex]\sf{1 + \dfrac{sin^2 x}{ cos^2 x }}[/tex]
[tex]\sf{\dfrac{cos^2 x + sin^2 x}{ cos^2 x }}[/tex]
We know that [tex]\sf{sin^2 x + cos^2 x = 1}[/tex]
Applying this identity, we get
[tex]\sf{\dfrac{1}{ cos^2 x }}[/tex]
Let’s move towards left side, LHS.
As said above in (2), so we can now substitute the value of secx to cosx.
[tex] \implies \sf{\dfrac{1}{ cos^2 x }}[/tex]
Now, compare LHS and RHS, it is same. So, we can say that [tex]\sf{sec^2 x = 1+ tan^2 x}[/tex]
Hence Proved!