Math1220 Midterm 1 Review Problems Answer Key 1. 2. 3. y=−4x+4+ π 2 3 1+5 √ x f −1( x)= 3 2−2 √ x (a) (b) (c) (d) (e) (f) (g) (h) 4. t= y'= 2cos (3x )(−sin (3x))(3) 3 + 2 cos (3x ) √1−(3x−2)2 5(2x 2 ) ) 5x +3 y ' =π (1+ x 4 )π−1 (4x 3 )+π1+x (ln π)(4x 3 ) y ' =−sech(cos (2x)) tanh(cos (2x ))(−sin (2x ))(2) 3 y'= −12x−7+12x 2−5cos(5x ) 3x−2 1 −1 1 y ' =e 3x + 3x (−3) 2 3x e 3x 2 (ln x ) 1 y ' =( x 3 −1)ln x ln (x 3 −1)+ 3 x x −1 −sin x y'= √( cos x+3)2−1 2 y ' =(5x +3)2x ( 4x ln (5x+3)+ 4 ( ) ( −10 ln(0.08) years ln 2 5. Evaluate each integral. 1 √ 1−4x 2+C 2 5 ln∣2x 2 +x−7∣+C −5arctan( ln x)+C 4−4−5 ln 16 1 2 ( y arctan ( y)− y +arctan ( y )) +C 2 −1 √ 3/2 ( 2 −2 ) ln 2 −1 ln 4 3 6 4−1 ln 36 1 ln (e 2x +5)+C 2 (a) x arcsin(2x )+ (b) (c) (d) (e) (f) (g) (h) (i) ) 5 (arcsin ( x 3 ))+C 3 1 x2 (k) arctan +C 4 2 1 ln ( x 4 +4)+C (l) 4 3 4x x (m) x (4 )− ln 4 ln 4 π (n) − 2 (j) ( ) ( 6. 1 14 7. f ( x )= ) sin x+1 and since sin x is always between -1 and 1, then 1+sin x must cos x be between 0 and 2 (inclusive) which is always nonnegative. The denominator is also always positive wherever the function actually exists. This means that the derivative is always nonnegative in the entire domain of the function. This is the same as saying that it's monotonic. 8. 9. 1 4 ( f ' ( x)=− 2 +15( x−1)2 1+4x 2 ) which is always positive inside the parentheses since all coefficients are positive and the powers on x are even. Thus, the derivative is always negative which means the inverse function exists. 10. ( ) 3 5x 15 =e x x →∞ 5x (b) lim ( 1 ) =1 (a) lim 1+ x →∞ ( f −1 )' (11)= 1 −1 = f ' (0) 17