Question 1076455
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5.7cos(x) + 4 = 1.15   --->

5.7*cos(x) = 1.15 - 4 --->

5.7*cos(x) = -2.85   --->

cos(x) = {{{(-2.85)/5.7}}}   --->

cos(x) = {{{-1/2}}}  --->

x = {{{2pi/3}}}    and/or   x = {{{4pi/3}}}. 
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