Ok here it goes
\[\tan x \sin x+ \cos x= \sec x\]
how can you rewrite tanx = ?
so tanx = sin x / cos x yes ?
\[\frac{ \sin x }{ \cos x }\]
than substitute in place of tanx what will get ?
cos x + cos x
no
check it please
\[\frac{ \sin x }{ \cos x } \sin x + \cos x\]
alryt looks like you guys gave up on me
yes but do you can continue it ?
Should you cancel something here?
multiplie sin x *sin x = ?
so than what you get ?
will be sin^2 x / cos x y
yes ?
Wait how was that?
so tanxsinx +cosx = secx because tanx = sinx / cos x sinx ---- *sinx +cosx = secx cosx sin^2 x ------ + cos x = sec x cos x yes ?
\[\large tan(x)sin(x) + cos(x) = sec(x)\] we know \(\large tan(x) = \frac{sin(x)}{cos(x)}\) so \[\large \frac{sin(x)}{cos(x)}\times sin(x) + cos(x) = sec(x)\] Multiply the sin/cos times sin \[\large \frac{sin^2(x)}{cos(x)} + cos(x) = sec(x)\] we need a common denominator to add those fractions...looks like cos(x) would be the best...so multiply the cos(x) by cos(x)/cos(x) \[\large \frac{sin^2(x)}{cos(x)} + \frac{cos^2(x)}{cos(x)} = sec(x)\] we can now place the fraations over the commondenominator \[\large \frac{sin^2(x) + cos^2(x)}{cos(x)} = sec(x)\] We know that \(\large sin^2(x) + cos^2(x) = 1 \) so \[\large \frac{1}{cos(x)} = sec(x)\] which is true...so the identity is verified
oh thx
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