Tanong # 9e7a0

Tanong # 9e7a0
Anonim

Sagot:

# x = 0,1.77,4.51,2pi #

Paliwanag:

Una, gagamitin natin ang pagkakakilanlan # tan ^ 2x = sec ^ 2x-1 #

# sec ^ 2x-1 + 4secx = 4 #

# sec ^ 2x + 4secx-5 = 0 #

# a = secx #

# a ^ 2 + 4a-5 = 0 #

# (a-1) (a + 5) = 0 #

# a = 1 o a = -5 #

# secx = 1 o secx = -5 #

# cosx = 1 o -1 / 5 #

# x = arccos (1) = 0 at 2pi #

o

# x = arccos (-1/5) ~~ 1.77 ^ c o ~ 4.51 ^ c #