REZOLVARE TESTUL 4 1) log2( 8) +(1/2) ^- 1 - ∛125 = 0    log2( 2³) + 2 - ∛5³ = 0    3 + 2 - 5 = 0    0 = 0 , verificat 2) f( x) = 2012x - 2011 A( 2013/2012, 2) ∈ Gf ⇒ f( 2013/ 2012) = 2, calculezi f ( 2013/2012) f ( 2013/2012) = 2012 · 2013/2012 - 2011                      = 2013 - 2011                      = 2 DECI VERIFICA RELATIA. 3) SUBMULTIMI:      B = { a,b,c}      C = { a,d,e}      E = { b,c,d} 4) ECUATIA EXPONENTIALA:   4^x - 10·2^x+ 16 = 0   2^2x - 10· 2^x + 16 = 0  se noteaza 2^x = y  y² - 10y + 16 = 0, ecuatie de gr. II   a = 1, b = - 10, c = 16   delta = b² - 4ac   delta = ( - 10)² - 4·1·16 = 100 - 64 = 36   delta = 36 ( > 0)   y1 = - b - √delta / 2a = 10 - √36 / 2 = 10 - 6 / 2 = 4/2 =2   y1 = 2   y2 = - b + √delta / 2a = 10 + √36 / 2 = 10 + 6 /2 = 16/2 = 8   y2 = 8   2^x = y1   2^x = 2 ⇒ x = 1  2^x = y2  2^x = 8 ⇒ 2^x = 2^3 ⇒ x = 3 DECI ECUATIA ARE DOUA SOLUTII : X = 1 SI X = 3