Prove that: (i) tan 20o tan 35o tan 45o tan 55o tan 70o=1 (ii) sin 48o

1.	Prove that: (i) tan 20o tan 35o tan 45o tan 55o tan 70o=1 (ii) sin 48o sec42o+cos 48o cosec 42o=2 (iii) sin 70ocos 20o+cosec 20osec 70o−2 cos 70o cosec 20o=0 (iv) cos 80osin 10o+cos 59o cosec 31o=2
Answer» Prove that: (i) tan $20^{o} t a n 35^{o} t a n 45^{o} t a n 55^{o} t a n 70^{o} = 1$ (ii) sin $48^{o} s e c 42^{o} + c o s 48^{o} c o s e c 42^{o} = 2$ (iii) $\frac{s i n 70^{o}}{c o s 20^{o}} + \frac{c o s e c 20^{o}}{s e c 70^{o}} - 2 c o s 70^{o} c o s e c 20^{o} = 0$ (iv) $\frac{c o s 80^{o}}{s i n 10^{o}} + c o s 59^{o} c o s e c 31^{o} = 2$

Prove that: (i) tan 20o tan 35o tan 45o tan 55o tan 70o=1 (ii) sin 48o sec42o+cos 48o cosec 42o=2 (iii) sin 70ocos 20o+cosec 20osec 70o−2 cos 70o cosec 20o=0 (iv) cos 80osin 10o+cos 59o cosec 31o=2

Answer»

Prove that:

(i) tan $20^{o} t a n 35^{o} t a n 45^{o} t a n 55^{o} t a n 70^{o} = 1$

(ii) sin $48^{o} s e c 42^{o} + c o s 48^{o} c o s e c 42^{o} = 2$

(iii) $\frac{s i n 70^{o}}{c o s 20^{o}} + \frac{c o s e c 20^{o}}{s e c 70^{o}} - 2 c o s 70^{o} c o s e c 20^{o} = 0$

(iv) $\frac{c o s 80^{o}}{s i n 10^{o}} + c o s 59^{o} c o s e c 31^{o} = 2$

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Prove that: (i) tan 20o tan 35o tan 45o tan 55o tan 70o=1 (ii) sin 48o sec42o+cos 48o cosec 42o=2 (iii) sin 70ocos 20o+cosec 20osec 70o−2 cos 70o cosec 20o=0 (iv) cos 80osin 10o+cos 59o cosec 31o=2

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