Find the exact solutions, in their simplest form, to the equations : a) 2ln(2x + 1)-4=0 b)7^(x)e^(4x)=e^5
a) 2ln(2x + 1)-4=0
-> ln(2x + 1)-2=0
-> ln(2x + 1)=2
-> (2x + 1)=e2
-> 2x = e2 -1
-> x = (e2 -1)/2
b) 7xe4x=e5
-> 7x=e5 \ e4x
-> 7x=e5-4x
-> ln(7x)=5-4x
-> xln(7)=5-4x
-> x(ln(7)+4)=5
-> x=5/(ln(7)+4)
EL
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