Q. Use Pascal's Triangle to expand (3y2−2)3. Express your answer in simplest form.Answer:
Identify Exponent Row: Identify the row of Pascal's Triangle that corresponds to the exponent 3. The third row of Pascal's Triangle (starting with row 0) is 1,3,3,1. These numbers will be the coefficients in the expansion.
Write Expansion Terms: Write out the terms of the expansion using the binomial theorem and the coefficients from Pascal's Triangle.The expansion will have four terms, with the coefficients 1, 3, 3, and 1, respectively. The first term will have (3y2)3, the second term will have (3y2)2 multiplied by −2, the third term will have (3y2) multiplied by (−2)2, and the fourth term will have (−2)3.
Calculate Each Term: Calculate each term of the expansion.First term: (3y2)3=27y6Second term: 3×(3y2)2×(−2)=3×9y4×(−2)=−54y4Third term: 3×(3y2)×(−2)2=3×3y2×4=36y2Fourth term: (−2)3=−8
Combine Terms: Combine all the terms to write the expanded form.The expanded form is 27y6−54y4+36y2−8.
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