Let f(x)=
{ sinx/x +cosx, x not equal to 0
 2, x=0.
Show that f(x) is continuous at x=0.

LHL = limx0- fx = limx0- sin xx + cos xPut x = 0-h, as x0-, then h0LHL = limh0sin0-h0-h + cos0-h=limh0- sin h-h + cos h=limh0sin hh + cos h=1 + cos 0=1 + 1=2RHL = limx0+ fx = limx0+ sin xx + cos xPut x = 0+h, as x0+, then h0LHL = limh0sin0+h0+h + cos0+h=limh0sin hh + cos h=1 + cos 0=1 + 1=2Now, f0 = 2Since, LHL = RHL = f0So, f is continuous at x = 0

 

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when limit tends zero sin x/x will be equal to 1 and cosx equals 1 , thus LHL = RHL as limit exits .therefore function is continuos at x=0. to make things easier draw graph
 
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