Question

No. 4 dan 5 jika bisa keduanya boleh langsung di jawab

Answer 1

4. ³log7 - 3 ³log3 + 1/2 ³log81 - ³log 63
 = ³log 7 - 3 + ³log9 - ³log (9x7)
= ³log 7 - 3 + 2 - ³log 9 - ³log 7
=-3 + 2 - 2
= -3

5. (x+2)² / (2x-3)² < 4²
x² + 4x + 4 < 16 (4x²-12x + 9)
x² + 4x + 4 < 64x² - 192x + 144
0 < 63x² - 196x + 140
0 < 9x² - 28x + 20
0 < (9x - 10) (x - 2)
x < 10/9    atau x < 2

Answer 2

4. ³log7 - 3 ³log3 + 1/2 ³log81 - ³log 63
 = ³log 7 - 3 + ³log9 - ³log (9x7)
= ³log 7 - 3 + 2 - ³log 9 - ³log 7 
=-3 + 2 - 2
= -3

5. (x+2)² / (2x-3)² < 4²
x² + 4x + 4 < 16 (4x²-12x + 9)
x² + 4x + 4 < 64x² - 192x + 144
0 < 63x² - 196x + 140
0 < 9x² - 28x + 20
0 < (9x - 10) (x - 2)
x < 10/9    atau x < 2